# nfctech (Standard NFC Technologies)
The **nfctech** module provides APIs for reading and writing tags that use different Near-Field Communication (NFC) technologies.
> **NOTE**
>
> The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.
## Modules to Import
```js
import tag from '@ohos.nfc.tag';
```
## NfcATag
Provides APIs to access NFC-A (ISO 14443-3A) properties and perform I/O operations on a tag. This class inherits from **[TagSession](js-apis-tagSession.md)**.
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **NfcATag**.
### NfcATag.getSak
getSak(): number
Obtains the SAK value of this NFC-A tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number | SAK value obtained. The SAK is a hexadecimal number ranging from **0x00** to **0xFF**.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'nfcA' correctly.
let sak = nfcA.getSak();
console.log("nfcA sak: " + sak);
```
### NfcATag.getAtqa
getAtqa(): number[]
Obtains the ATQA value of this NFC-A tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number[] | ATQA value obtained. Each number of the ATQA is a hexadecimal number ranging from **0x00** to **0xFF**.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'nfcA' correctly.
let atqa = nfcA.getAtqa();
console.log("nfcA atqa: " + atqa);
```
## NfcBTag
Provides APIs to access NFC-B (ISO 14443-3B) properties and perform I/O operations on a tag. This class inherits from **TagSession**.
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **NfcBTag**.
### NfcBTag.getRespAppData
getRespAppData(): number[]
Obtains the application data of this NFC-B tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number[] | Application data obtained, which consists of hexadecimal numbers ranging from **0x00** to **0xFF**.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'nfcB' correctly.
let respAppData = nfcB.getRespAppData();
console.log("nfcB respAppData: " + respAppData);
```
### NfcBTag.getRespProtocol
getRespProtocol(): number[]
Obtains the protocol information of this NFC-B tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number[] | Protocol information obtained, which consists of hexadecimal numbers ranging from **0x00** to **0xFF**.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'nfcB' correctly.
let respProtocol = nfcB.getRespProtocol();
console.log("nfcB respProtocol: " + respProtocol);
```
## NfcFTag
Provides APIs to access NFC-F (JIS 6319-4) properties and perform I/O operations on a tag. This class inherits from **TagSession**.
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **NfcFTag**.
### NfcFTag.getSystemCode
getSystemCode(): number[]
Obtains the system code from this NFC-F tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number[] | System code obtained, which consists of hexadecimal numbers ranging from **0x00** to **0xFF**.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'nfcF' correctly.
let systemCode = nfcF.getSystemCode();
console.log("nfcF systemCode: " + systemCode);
```
### NfcFTag.getPmm
getPmm(): number[]
Obtains the PMm (consisting of the IC code and manufacturer parameters) information from this NFC-F tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number[] | PMm information obtained, which consists of hexadecimal numbers ranging from **0x00** to **0xFF**.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'nfcF' correctly.
let pmm = nfcF.getPmm();
console.log("nfcF pmm: " + pmm);
```
## NfcVTag
Provides APIs to access NFC-V (ISO 15693) properties and perform I/O operations on a tag. This class inherits from **TagSession**.
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **NfcVTag**.
### NfcvTag.getResponseFlags
getResponseFlags(): number
Obtains the response flags from this NFC-V tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number | Response flags obtained, which consist of hexadecimal numbers ranging from **0x00** to **0xFF**.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'nfcV' correctly.
let responseFlags = nfcV.getResponseFlags();
console.log("nfcV responseFlags: " + responseFlags);
```
### NfcvTag.getDsfId
getDsfId(): number
Obtains the data storage format identifier (DSFID) from this NFC-V tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number | DSFID obtained, which consists of hexadecimal numbers ranging from **0x00** to **0xFF**.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'nfcV' correctly.
let dsfId = nfcV.getDsfId();
console.log("nfcV dsfId: " + dsfId);
```
## IsoDepTag9+
Provides APIs to access ISO-DEP (ISO 14443-4) properties and I/O operations on a tag. This class inherits from **TagSession**.
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **IsoDepTag**.
### IsoDepTag.getHistoricalBytes9+
getHistoricalBytes(): number[]
Obtains the historical bytes for the given tag. This API applies only to the IsoDep cards that use the NFC-A technology.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number[] | Historical bytes obtained, which consist of hexadecimal numbers ranging from **0x00** to **0xFF**. If the IsoDep tag uses the NFC-B technology, **null** will be returned.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'isoDep' correctly.
let historicalBytes = isoDep.getHistoricalBytes();
console.log("isoDep historicalBytes: " + historicalBytes);
```
### IsoDepTag.getHiLayerResponse9+
getHiLayerResponse(): number[]
Obtains the higher-layer response bytes for the given tag. This API applies only to the IsoDep cards that use the NFC-B technology.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number[] | Higher-layer response bytes obtained, which consist of hexadecimal numbers ranging from **0x00** to **0xFF**. If the IsoDep tag uses the NFC-A technology, **null** will be returned.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'isoDep' correctly.
let hiLayerResponse = isoDep.getHiLayerResponse();
console.log("isoDep hiLayerResponse: " + hiLayerResponse);
```
### IsoDepTag.isExtendedApduSupported9+
isExtendedApduSupported(): Promise<boolean>
Checks whether an extended application protocol data unit (APDU) is supported. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| Promise<boolean> | Promise used to return the result. If the extended APDU is supported, **true** is returned; otherwise, **false** is returned.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'isoDep' correctly.
// Connect to the tag if it is not connected.
if (!isoDep.isTagConnected()) {
if (!isoDep.connectTag()) {
console.log("isoDep connectTag failed.");
return;
}
}
try {
isoDep.isExtendedApduSupported().then((response) => {
console.log("isoDep isExtendedApduSupported Promise response: " + response);
}).catch((err)=> {
console.log("isoDep isExtendedApduSupported Promise err: " + err);
});
} catch (busiError) {
console.log("isoDep isExtendedApduSupported Promise busiError: " + busiError);
}
```
### IsoDepTag.isExtendedApduSupported9+
isExtendedApduSupported(callback: AsyncCallback\): void
Checks whether an extended APDU is supported. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| callback | AsyncCallback\ | Yes | Callback invoked to return the result. If the extended APDU is supported, **true** is returned; otherwise, **false** is returned.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'isoDep' correctly.
// Connect to the tag if it is not connected.
if (!isoDep.isTagConnected()) {
if (!isoDep.connectTag()) {
console.log("isoDep connectTag failed.");
return;
}
}
try {
isoDep.isExtendedApduSupported((err, response)=> {
if (err) {
console.log("isoDep isExtendedApduSupported AsyncCallback err: " + err);
} else {
console.log("isoDep isExtendedApduSupported AsyncCallback response: " + response);
}
});
} catch (busiError) {
console.log("isoDep isExtendedApduSupported AsyncCallback busiError: " + busiError);
}
```
## NdefMessage9+
### NdefMessage.getNdefRecords9+
getNdefRecords(): [tag.NdefRecord](js-apis-nfcTag.md#ndefrecord9)[]
Obtains all NDEF records.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| [tag.NdefRecord](js-apis-nfcTag.md#ndefrecord9)[] | List of NDEF records obtained. For details, see *NFCForum-TS-NDEF_1.0*.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Obtain ndefMessage from tag.ndef.createNdefMessage or ndefTag.getNdefMessage.
// var ndefMessage = tag.ndef.createNdefMessage(...);
// var ndefMessage = ndefTag.getNdefMessage();
let ndefRecords = ndefMessage.getNdefRecords();
console.log("ndef ndefRecords number: " + ndefRecords.length);
```
## NdefTag9+
Provides APIs to access the tags in the NFC Data Exchange Format (NDEF). This class inherits from **TagSession**.
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **NdefTag**.
### NdefTag.getNdefTagType9+
getNdefTagType(): [tag.NfcForumType](js-apis-nfcTag.md#nfcforumtype9)
Obtains the NDEF tag type.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| [tag.NfcForumType](js-apis-nfcTag.md#nfcforumtype9) | NDEF tag type obtained. It can be NFC FORUM TYPE 1, 2, 3, or 4.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
let ndefTagType = ndefTag.getNdefTagType();
console.log("ndef ndefTagType: " + ndefTagType);
```
### NdefTag.getNdefMessage9+
getNdefMessage(): [NdefMessage](#ndefmessage9)
Obtains the NDEF message from this NDEF tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| [NdefMessage](#ndefmessage9) | NDEF message created. For details, see *NFCForum-TS-NDEF_1.0*.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
let ndefMessage = ndefTag.getNdefMessage();
console.log("ndef ndefMessage: " + ndefMessage);
```
### NdefTag.isNdefWritable9+
isNdefWritable(): boolean;
Check whether this NDEF tag is writable. Before calling the data write API, check whether the write operation is supported.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| boolean | Promise used to return the result. If the tag is writable, **true** is returned; otherwise, **false** is returned.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
var isWritable = ndefTag.isNdefWritable();
console.log("ndef isNdefWritable: " + isWritable);
```
### NdefTag.readNdef9+
readNdef(): Promise\<[NdefMessage](#ndefmessage9)>
Reads the NDEF message from this tag. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| Promise\<[NdefMessage](#ndefmessage9)> | Promise used to return the message read.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
// Connect to the tag if it is not connected.
if (!ndefTag.isTagConnected()) {
if (!ndefTag.connectTag()) {
console.log("ndefTag connectTag failed.");
return;
}
}
try {
ndefTag.readNdef().then((ndefmessage) => {
console.log("ndef readNdef Promise ndefmessage: " + ndefmessage);
}).catch((err)=> {
console.log("ndef readNdef Promise err: " + err);
});
} catch (busiError) {
console.log("ndef readNdef Promise catched busiError: " + busiError);
}
```
### NdefTag.readNdef9+
readNdef(callback: AsyncCallback\<[NdefMessage](#ndefmessage9)>): void
Reads the NDEF message from this tag. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| callback | AsyncCallback\<[NdefMessage](#ndefmessage9)> | Yes | Callback invoked to return the NDEF message read.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
// Connect to the tag if it is not connected.
if (!ndefTag.isTagConnected()) {
if (!ndefTag.connectTag()) {
console.log("ndefTag connectTag failed.");
return;
}
}
try {
ndefTag.readNdef((err, ndefmessage)=> {
if (err) {
console.log("ndef readNdef AsyncCallback err: " + err);
} else {
console.log("ndef readNdef AsyncCallback ndefmessage: " + ndefmessage);
}
});
} catch (busiError) {
console.log("ndef readNdef AsyncCallback catched busiError: " + busiError);
}
```
### NdefTag.writeNdef9+
writeNdef(msg: NdefMessage): Promise\;
Writes an NDEF message to this tag. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| msg | NdefMessage | Yes | NDEF message to write.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
// NDEF message created from raw data, such as:
let ndefMessage = tag.ndef.createNdefMessage([0xD1, 0x01, 0x03, 0x54, 0x4E, 0x46, 0x43]); // It must be parsed as NDEF Record.
// or ndefMessage created from tag.ndef.createNdefMessage(ndefRecords: NdefRecord[])
// Connect to the tag if it is not connected.
if (!ndefTag.isTagConnected()) {
if (!ndefTag.connectTag()) {
console.log("ndefTag connectTag failed.");
return;
}
}
try {
ndefTag.writeNdef(ndefMessage).then(() => {
console.log("ndef writeNdef Promise success.");
}).catch((err)=> {
console.log("ndef writeNdef err: " + err);
});
} catch (busiError) {
console.log("ndef writeNdef Promise catch busiError: " + busiError);
}
```
### NdefTag.writeNdef9+
writeNdef(msg: [NdefMessage](#ndefmessage9), callback: AsyncCallback\): void
Writes an NDEF message to this tag. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| msg | [NdefMessage](#ndefmessage9) | Yes | NDEF message to write.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
// NDEF message created from raw data, such as:
let ndefMessage = tag.ndef.createNdefMessage([0xD1, 0x01, 0x03, 0x54, 0x4E, 0x46, 0x43]); // It must be parsed as NDEF Record.
// or ndefMessage created from tag.ndef.createNdefMessage(ndefRecords: NdefRecord[])
// Connect to the tag if it is not connected.
if (!ndefTag.isTagConnected()) {
if (!ndefTag.connectTag()) {
console.log("ndefTag connectTag failed.");
return;
}
}
try {
ndefTag.writeNdef(ndefMessage, (err)=> {
if (err) {
console.log("ndef writeNdef AsyncCallback err: " + err);
} else {
console.log("ndef writeNdef AsyncCallback success.");
}
});
} catch (busiError) {
console.log("ndef writeNdef AsyncCallback catch busiError: " + busiError);
}
```
### NdefTag.canSetReadOnly9+
canSetReadOnly(): boolean
Checks whether this NDEF tag can be set to read-only.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| boolean| Returns **true** if the tag can be set to read-only; returns **false** otherwise.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
var canSetReadOnly = ndefTag.canSetReadOnly();
console.log("ndef canSetReadOnly: " + canSetReadOnly);
```
### NdefTag.setReadOnly9+
setReadOnly(): Promise\
Sets this NDEF tag to read-only. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
// Connect to the tag if it is not connected.
if (!ndefTag.isTagConnected()) {
if (!ndefTag.connectTag()) {
console.log("ndefTag connectTag failed.");
return;
}
}
try {
ndefTag.setReadOnly().then(() => {
console.log("ndef setReadOnly Promise success.");
}).catch((err)=> {
console.log("ndef setReadOnly Promise err: " + err);
});
} catch (busiError) {
console.log("ndef setReadOnly Promise catch busiError: " + busiError);
}
```
### NdefTag.setReadOnly9+
setReadOnly(callback: AsyncCallback\): void
Sets this NDEF tag to read-only. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| callback | AsyncCallback\ | Yes | Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
// Connect to the tag if it is not connected.
if (!ndefTag.isTagConnected()) {
if (!ndefTag.connectTag()) {
console.log("ndefTag connectTag failed.");
return;
}
}
try {
ndefTag.setReadOnly((err)=> {
if (err) {
console.log("ndef setReadOnly AsyncCallback err: " + err);
} else {
console.log("ndef setReadOnly AsyncCallback success.");
}
});
} catch (busiError) {
console.log("ndef setReadOnly AsyncCallback catch busiError: " + busiError);
}
```
### NdefTag.getNdefTagTypeString9+
getNdefTagTypeString(type: [tag.NfcForumType](js-apis-nfcTag.md#nfcforumtype9)): string
Converts an NFC Forum Type tag to a string defined in the NFC Forum.
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| type | [tag.NfcForumType](js-apis-nfcTag.md#nfcforumtype9) | Yes | NDEF tag type. It can be NFC FORUM type 1, 2, 3, or 4.|
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| string | Byte array obtained.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefTag' correctly.
try {
let ndefTypeString = ndefTag.getNdefTagTypeString(tag.NFC_FORUM_TYPE_1);
console.log("ndef ndefTypeString: " + ndefTypeString);
} catch (busiError) {
console.log("ndef getNdefTagTypeString catch busiError: " + busiError);
}
```
## MifareClassicTag9+
Provides APIs to access MIFARE Classic properties and perform I/O operations on a tag. This class inherits from [TagSession](js-apis-tagSession.md).
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **MifareClassicTag**.
### MifareClassicTag.authenticateSector9+
authenticateSector(sectorIndex: number, key: number[], isKeyA: boolean): Promise\
Authenticates a sector using a key. The sector can be accessed only after the authentication is successful. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| sectorIndex | number | Yes | Index of the sector to authenticate. The sector indexes start from **0**.|
| key | number[]| Yes | Key (6 bytes) used for sector authentication.|
| isKeyA | boolean | Yes | Whether the key is key A. The value **true** indicates key A, and **false** indicates key B.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let sectorIndex = 1; // Change it as required.
let key = [0x01, 0x02, 0x03, 0x04, 0x05, 0x06] // The key must be of 6 bytes.
mifareClassic.authenticateSector(sectorIndex, key, true).then(() => {
console.log("mifareClassic authenticateSector Promise success.");
}).catch((err)=> {
console.log("mifareClassic authenticateSector Promise err: " + err);
});
} catch (busiError) {
console.log("mifareClassic authenticateSector Promise catch busiError: " + busiError);
}
```
### MifareClassicTag.authenticateSector9+
authenticateSector(sectorIndex: number, key: number[], isKeyA: boolean, callback: AsyncCallback\): void
Authenticates a sector using a key. The sector can be accessed only after the authentication is successful. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| sectorIndex | number | Yes | Index of the sector to authenticate. The sector indexes start from **0**.|
| key | number[]| Yes | Key (6 bytes) used for sector authentication.|
| isKeyA | boolean | Yes | Whether the key is key A. The value **true** indicates key A, and **false** indicates key B.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let sectorIndex = 1; // Change it as required.
let key = [0x01, 0x02, 0x03, 0x04, 0x05, 0x06] // The key must be of 6 bytes.
mifareClassic.authenticateSector(sectorIndex, key, true, (err)=> {
if (err) {
console.log("mifareClassic authenticateSector AsyncCallback err: " + err);
} else {
console.log("mifareClassic authenticateSector AsyncCallback success.");
}
});
} catch (busiError) {
console.log("mifareClassic authenticateSector AsyncCallback catch busiError: " + busiError);
}
```
### MifareClassicTag.readSingleBlock9+
readSingleBlock(blockIndex: number): Promise\
Reads a block (16 bytes) on this tag. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the block to read. The block indexes start from **0**.|
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| Promise\ | Promise used to return the block data read.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
mifareClassic.readSingleBlock(blockIndex).then((data) => {
console.log("mifareClassic readSingleBlock Promise data: " + data);
}).catch((err)=> {
console.log("mifareClassic readSingleBlock Promise err: " + err);
});
} catch (busiError) {
console.log("mifareClassic readSingleBlock Promise catch busiError: " + busiError);
}
```
### MifareClassicTag.readSingleBlock9+
readSingleBlock(blockIndex: number, callback: AsyncCallback\): void
Reads a block (16 bytes) on this tag. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the block to read. The block indexes start from **0**.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the data read.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
mifareClassic.readSingleBlock(blockIndex, (err, data)=> {
if (err) {
console.log("mifareClassic readSingleBlock AsyncCallback err: " + err);
} else {
console.log("mifareClassic readSingleBlock AsyncCallback data: " + data);
}
});
} catch (busiError) {
console.log("mifareClassic readSingleBlock AsyncCallback catch busiError: " + busiError);
}
```
### MifareClassicTag.writeSingleBlock9+
writeSingleBlock(blockIndex: number, data: number[]): Promise\
Writes data to a block on this tag. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the target block. The block indexes start from **0**.|
| data | number[] | Yes | 16-byte data to write.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
let rawData = [0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A,
0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10]; // MUST be 16 bytes, change it to be correct data.
mifareClassic.writeSingleBlock(blockIndex, rawData).then(() => {
console.log("mifareClassic writeSingleBlock Promise success.");
}).catch((err)=> {
console.log("mifareClassic writeSingleBlock Promise err: " + err);
});
} catch (busiError) {
console.log("mifareClassic writeSingleBlock Promise catch busiError: " + busiError);
}
```
### MifareClassicTag.writeSingleBlock9+
writeSingleBlock(blockIndex: number, data: number[], callback: AsyncCallback\): void
Writes data to a block on this tag. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the target block. The block indexes start from **0**.|
| data | number[] | Yes | 16-byte data to write.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
let rawData = [0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A,
0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10]; // MUST be 16 bytes, change it to be correct data.
mifareClassic.writeSingleBlock(blockIndex, rawData, (err)=> {
if (err) {
console.log("mifareClassic writeSingleBlock AsyncCallback err: " + err);
} else {
console.log("mifareClassic writeSingleBlock AsyncCallback success.");
}
});
} catch (busiError) {
console.log("mifareClassic writeSingleBlock AsyncCallback catch busiError: " + busiError);
}
```
### MifareClassicTag.incrementBlock9+
incrementBlock(blockIndex: number, value: number): Promise\
Increments a block with data. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the block to increment. The block indexes start from **0**.|
| value | number | Yes | Block data to increment. The value cannot be a negative number.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
let value = 0x20; // Change it as required.
mifareClassic.incrementBlock(blockIndex, value).then(() => {
console.log("mifareClassic incrementBlock Promise success.");
}).catch((err)=> {
console.log("mifareClassic incrementBlock Promise err: " + err);
});
} catch (busiError) {
console.log("mifareClassic incrementBlock Promise catch busiError: " + busiError);
}
```
### MifareClassicTag.incrementBlock9+
incrementBlock(blockIndex: number, value: number, callback: AsyncCallback\): void
Increments a block with data. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the block to increment. The block indexes start from **0**.|
| value | number | Yes | Block data to increment. The value cannot be a negative number.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
let value = 0x20; // Change it as required.
mifareClassic.incrementBlock(blockIndex, value, (err)=> {
if (err) {
console.log("mifareClassic incrementBlock AsyncCallback err: " + err);
} else {
console.log("mifareClassic incrementBlock AsyncCallback success.");
}
});
} catch (busiError) {
console.log("mifareClassic incrementBlock AsyncCallback catch busiError: " + busiError);
}
```
### MifareClassicTag.decrementBlock9+
decrementBlock(blockIndex: number, value: number): Promise\
Decrements a block. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the block to decrement. The block indexes start from **0**.|
| value | number | Yes | Block data to decrement. The value cannot be a negative number.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
let value = 0x20; // Change it as required.
mifareClassic.decrementBlock(blockIndex, value).then(() => {
console.log("mifareClassic decrementBlock Promise success.");
}).catch((err)=> {
console.log("mifareClassic decrementBlock Promise err: " + err);
});
} catch (busiError) {
console.log("mifareClassic decrementBlock Promise catch busiError: " + busiError);
}
```
### MifareClassicTag.decrementBlock9+
decrementBlock(blockIndex: number, value: number, callback: AsyncCallback\): void
Decrements a block. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the block to decrement. The block indexes start from **0**.|
| value | number | Yes | Block data to decrement. The value cannot be a negative number.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
let value = 0x20; // Change it as required.
mifareClassic.decrementBlock(blockIndex, value, (err)=> {
if (err) {
console.log("mifareClassic decrementBlock AsyncCallback err: " + err);
} else {
console.log("mifareClassic decrementBlock AsyncCallback success.");
}
});
} catch (busiError) {
console.log("mifareClassic decrementBlock AsyncCallback catch busiError: " + busiError);
}
```
### MifareClassicTag.transferToBlock9+
transferToBlock(blockIndex: number): Promise\
Transfers data from the temporary register to a block. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the destination block. The value starts form **0**.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
mifareClassic.transferToBlock(blockIndex).then(() => {
console.log("mifareClassic transferToBlock Promise success.");
}).catch((err)=> {
console.log("mifareClassic transferToBlock Promise err: " + err);
});
} catch (busiError) {
console.log("mifareClassic transferToBlock Promise catch busiError: " + busiError);
}
```
### MifareClassicTag.transferToBlock9+
transferToBlock(blockIndex: number, callback: AsyncCallback\): void
Transfers data from the temporary register to a block. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the destination block. The value starts form **0**.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
mifareClassic.transferToBlock(blockIndex, (err)=> {
if (err) {
console.log("mifareClassic transferToBlock AsyncCallback err: " + err);
} else {
console.log("mifareClassic transferToBlock AsyncCallback success.");
}
});
} catch (busiError) {
console.log("mifareClassic transferToBlock AsyncCallback catch busiError: " + busiError);
}
```
### MifareClassicTag.restoreFromBlock9+
restoreFromBlock(blockIndex: number): Promise\
Restores data in the temporary register from a block. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the target block. The value starts form **0**.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
mifareClassic.restoreFromBlock(blockIndex).then(() => {
console.log("mifareClassic restoreFromBlock Promise success.");
}).catch((err)=> {
console.log("mifareClassic restoreFromBlock Promise err: " + err);
});
} catch (busiError) {
console.log("mifareClassic restoreFromBlock Promise catch busiError: " + busiError);
}
```
### MifareClassicTag.restoreFromBlock9+
restoreFromBlock(blockIndex: number, callback: AsyncCallback\): void
Restores data in the temporary register from a block. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes | Index of the target block. The value starts form **0**.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
// Connect to the tag if it is not connected.
if (!mifareClassic.isTagConnected()) {
if (!mifareClassic.connectTag()) {
console.log("mifareClassic connectTag failed.");
return;
}
}
try {
let blockIndex = 1; // Change it as required.
mifareClassic.restoreFromBlock(blockIndex, (err)=> {
if (err) {
console.log("mifareClassic restoreFromBlock AsyncCallback err: " + err);
} else {
console.log("mifareClassic restoreFromBlock AsyncCallback success.");
}
});
} catch (busiError) {
console.log("mifareClassic restoreFromBlock AsyncCallback catch busiError: " + busiError);
}
```
### MifareClassicTag.getSectorCount9+
getSectorCount(): number
Obtains the number of sectors in this MIFARE Classic tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number | Number of sectors obtained.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
let sectorCount = mifareClassic.getSectorCount();
console.log("mifareClassic sectorCount: " + sectorCount);
```
### MifareClassicTag.getBlockCountInSector9+
getBlockCountInSector(sectorIndex: number): number
Obtains the number of blocks in a sector.
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| sectorIndex | number | Yes | Index of the target sector. The sector indexes start from **0**.|
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number | Number of blocks obtained.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
try {
let sectorIndex = 1; // Change it as required.
let blockCnt = mifareClassic.getBlockCountInSector(sectorIndex);
console.log("mifareClassic blockCnt: " + blockCnt);
} catch (busiError) {
console.log("mifareClassic getBlockCountInSector catch busiError: " + busiError);
}
```
### MifareClassicTag.getType9+
getType(): [tag.MifareClassicType](js-apis-nfcTag.md#mifareclassictype9)
Obtains the type of this MIFARE Classic tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| [tag.MifareClassicType](js-apis-nfcTag.md#mifareclassictype9) | Type of the MIFARE Classic tag obtained.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
let getType = mifareClassic.getType();
console.log("mifareClassic getType: " + getType);
```
### MifareClassicTag.getTagSize9+
getTagSize(): number
Obtains the size of this tag. For details, see [MifareClassicSize](js-apis-nfcTag.md#mifareclassicsize9).
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number | Tag size obtained, in bytes. For details, see [MifareClassicSize](js-apis-nfcTag.md#mifareclassicsize9).|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
let tagSize = mifareClassic.getTagSize();
console.log("mifareClassic tagSize: " + tagSize);
```
### MifareClassicTag.isEmulatedTag9+
isEmulatedTag(): boolean
Checks whether it is an emulated tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| boolean |Returns **true** if the tag is an emulated tag; returns **false** otherwise.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
let isEmulatedTag = mifareClassic.isEmulatedTag();
console.log("mifareClassic isEmulatedTag: " + isEmulatedTag);
```
### MifareClassicTag.getBlockIndex9+
getBlockIndex(sectorIndex: number): number
Obtains the index of the first block in a sector.
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| sectorIndex | number | Yes | Index of the target sector. The sector indexes start from **0**.|
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number | Index of the first block obtained.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
try {
let sectorIndex = 1; // Change it as required.
let blockIndex = mifareClassic.getBlockIndex(sectorIndex);
console.log("mifareClassic blockIndex: " + blockIndex);
} catch (busiError) {
console.log("mifareClassic getBlockIndex catch busiError: " + busiError);
}
```
### MifareClassicTag.getSectorIndex9+
getSectorIndex(blockIndex: number): number
Obtains the index of the sector that holds the specified block.
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| blockIndex | number | Yes| Index of the block. The block indexes start from **0**.|
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| number | Index of the sector obtained.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareClassic' correctly.
try {
let blockIndex = 1; // Change it as required.
let sectorIndex = mifareClassic.getSectorIndex(blockIndex);
console.log("mifareClassic sectorIndex: " + sectorIndex);
} catch (busiError) {
console.log("mifareClassic getSectorIndex catch busiError: " + busiError);
}
```
## MifareUltralightTag9+
Provides APIs to access MIFARE Ultralight properties and perform I/O operations on a tag. This class inherits from **TagSession**.
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **MifareUltralightTag**.
### MifareUltralightTag.readMultiplePages9+
readMultiplePages(pageIndex: number): Promise\
Reads four pages (4 bytes per page) from this tag. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | ------------------------------ |
| pageIndex | number | Yes | Index of the first page to read. The page indexes start from **0**.|
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| Promise\ | Promise used to return the data read, which is 16 bytes in total.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareUltralight' correctly.
// Connect to the tag if it is not connected.
if (!mifareUltralight.isTagConnected()) {
if (!mifareUltralight.connectTag()) {
console.log("mifareUltralight connectTag failed.");
return;
}
}
try {
let pageIndex = 1; // Change it as required.
mifareUltralight.readMultiplePages(pageIndex).then((data) => {
console.log("mifareUltralight readMultiplePages Promise data = " + data);
}).catch((err)=> {
console.log("mifareUltralight readMultiplePages Promise err: " + err);
});
} catch (busiError) {
console.log("mifareUltralight readMultiplePages Promise catch busiError: " + busiError);
}
```
### MifareUltralightTag.readMultiplePages9+
readMultiplePages(pageIndex: number, callback: AsyncCallback\): void
Reads four pages (4 bytes per page) from this tag. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| pageIndex | number | Yes | Index of the first page to read. The page indexes start from **0**.|
| callback | AsyncCallback\ | Yes | Callback invoked to return the data read, which is 16 bytes in total.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareUltralight' correctly.
// Connect to the tag if it is not connected.
if (!mifareUltralight.isTagConnected()) {
if (!mifareUltralight.connectTag()) {
console.log("mifareUltralight connectTag failed.");
return;
}
}
try {
let pageIndex = 1; // Change it as required.
mifareUltralight.readMultiplePages(pageIndex, (err, data)=> {
if (err) {
console.log("mifareUltralight readMultiplePages AsyncCallback err: " + err);
} else {
console.log("mifareUltralight readMultiplePages AsyncCallback data: " + data);
}
});
} catch (busiError) {
console.log("mifareUltralight readMultiplePages AsyncCallback catch busiError: " + busiError);
}
```
### MifareUltralightTag.writeSinglePage9+
writeSinglePage(pageIndex: number, data: number[]): Promise\
Writes one page (4 bytes) of data to this tag. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| pageIndex | number | Yes | Index of the page to write. The page indexes start from **0**.|
| data | number[] | Yes | 4-byte data to write.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareUltralight' correctly.
// Connect to the tag if it is not connected.
if (!mifareUltralight.isTagConnected()) {
if (!mifareUltralight.connectTag()) {
console.log("mifareUltralight connectTag failed.");
return;
}
}
try {
let pageIndex = 1; // Change it as required.
let rawData = [0x01, 0x02, 0x03, 0x04]; // MUST be 4 bytes, change it to be correct raw data.
mifareUltralight.writeSinglePage(pageIndex, rawData).then(() => {
console.log("mifareUltralight writeSinglePage Promise success.");
}).catch((err)=> {
console.log("mifareUltralight writeSinglePage Promise err: " + err);
});
} catch (busiError) {
console.log("mifareUltralight writeSinglePage Promise catch busiError: " + busiError);
}
```
### MifareUltralightTag.writeSinglePage9+
writeSinglePage(pageIndex: number, data: number[], callback: AsyncCallback\): void
Writes one page (4 bytes) of data to this tag. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | ------------------------ |
| pageIndex | number | Yes | Index of the page to write. The page indexes start from **0**.|
| data | number[] | Yes | 4-byte data to write.|
| callback|AsyncCallback\ |Yes| Callback invoked to return the result.|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareUltralight' correctly.
// Connect to the tag if it is not connected.
if (!mifareUltralight.isTagConnected()) {
if (!mifareUltralight.connectTag()) {
console.log("mifareUltralight connectTag failed.");
return;
}
}
try {
let pageIndex = 1; // Change it as required.
let rawData = [0x01, 0x02, 0x03, 0x04]; // MUST be 4 bytes, change it to be correct raw data.
mifareUltralight.writeSinglePage(pageIndex, rawData, (err)=> {
if (err) {
console.log("mifareUltralight writeSinglePage AsyncCallback err: " + err);
} else {
console.log("mifareUltralight writeSinglePage AsyncCallback success.");
}
});
} catch (busiError) {
console.log("mifareUltralight writeSinglePage AsyncCallback catch busiError: " + busiError);
}
```
### MifareUltralightTag.getType9+
getType(): [tag.MifareUltralightType](js-apis-nfcTag.md#mifareultralighttype9)
Obtains the type of this MIFARE Ultralight tag.
**System capability**: SystemCapability.Communication.NFC.Tag
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| [tag.MifareUltralightType](js-apis-nfcTag.md#mifareultralighttype9) | Type of the MIFARE Ultralight tag obtained.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'mifareUltralight' correctly.
let getType = mifareClassic.getType();
console.log("mifareUltralight getType: " + getType);
```
## NdefFormatableTag9+
Provides APIs for formatting NDEF formattable tags. This class inherits from **TagSession**.
**TagSession** is the base class of all NFC tag technologies. It provides common interfaces for establishing connections and transferring data. For more details, see [TagSession](js-apis-tagSession.md).
The following describes the unique APIs of **NdefFormatableTag**.
### NdefFormatableTag.format9+
format(message: [NdefMessage](#ndefmessage9)): Promise\
Formats this tag as an NDEF tag, and writes an NDEF message to it. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| message | [NdefMessage](#ndefmessage9) | Yes | NDEF message to write. If this parameter is **null**, the tag is formatted only (no data will be written).|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefFormatable' correctly.
// Connect to the tag if it is not connected.
if (!ndefFormatable.isTagConnected()) {
if (!ndefFormatable.connectTag()) {
console.log("ndefFormatable connectTag failed.");
return;
}
}
try {
// NDEF message created from raw data, such as:
let ndefMessage = tag.ndef.createNdefMessage([0xD1, 0x01, 0x03, 0x54, 0x4E, 0x46, 0x43]); // It must be parsed as NDEF Record.
// or ndefMessage created from tag.ndef.createNdefMessage(ndefRecords: NdefRecord[])
ndefFormatable.format(ndefMessage).then(() => {
console.log("ndefFormatable format Promise success.");
}).catch((err)=> {
console.log("ndefFormatable format Promise err: " + err);
});
} catch (busiError) {
console.log("ndefFormatable format Promise catch busiError: " + busiError);
}
```
### NdefFormatableTag.format9+
format(message: [NdefMessage](#ndefmessage9), callback: AsyncCallback\): void
Formats this tag as an NDEF tag, and writes an NDEF message to it. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| message | [NdefMessage](#ndefmessage9) | Yes | NDEF message to write when the formatting is successful. If this parameter is **null**, the tag is formatted only (no data will be written).|
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| callback: AsyncCallback\ | Callback invoked to return the result.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefFormatable' correctly.
// Connect to the tag if it is not connected.
if (!ndefFormatable.isTagConnected()) {
if (!ndefFormatable.connectTag()) {
console.log("ndefFormatable connectTag failed.");
return;
}
}
try {
// NDEF message created from raw data, such as:
let ndefMessage = tag.ndef.createNdefMessage([0xD1, 0x01, 0x03, 0x54, 0x4E, 0x46, 0x43]); // It must be parsed as NDEF Record.
// or ndefMessage created from tag.ndef.createNdefMessage(ndefRecords: NdefRecord[])
ndefFormatable.format(ndefMessage, (err)=> {
if (err) {
console.log("ndefFormatable format AsyncCallback err: " + err);
} else {
console.log("ndefFormatable format AsyncCallback success.");
}
});
} catch (busiError) {
console.log("ndefFormatable format AsyncCallback catch busiError: " + busiError);
}
```
### NdefFormatableTag.formatReadOnly9+
formatReadOnly(message: [NdefMessage](#ndefmessage9)): Promise\
Formats this tag as an NDEF tag, writes an NDEF message to it, and then sets the tag to read-only. This API uses a promise to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| message | [NdefMessage](#ndefmessage9) | Yes | NDEF message to write. If this parameter is **null**, the tag is formatted only (no data will be written).|
**Error codes**
For details about the error codes, see [NFC Error Codes](../errorcodes/errorcode-nfc.md).
| ID| Error Message|
| ------- | -------|
| 3100201 | Tag running state is abnormal in service. |
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefFormatable' correctly.
// Connect to the tag if it is not connected.
if (!ndefFormatable.isTagConnected()) {
if (!ndefFormatable.connectTag()) {
console.log("ndefFormatable connectTag failed.");
return;
}
}
try {
// NDEF message created from raw data, such as:
let ndefMessage = tag.ndef.createNdefMessage([0xD1, 0x01, 0x03, 0x54, 0x4E, 0x46, 0x43]); // It must be parsed as NDEF Record.
// or ndefMessage created from tag.ndef.createNdefMessage(ndefRecords: NdefRecord[])
ndefFormatable.formatReadOnly(ndefMessage).then(() => {
console.log("ndefFormatable formatReadOnly Promise success.");
}).catch((err)=> {
console.log("ndefFormatable formatReadOnly Promise err: " + err);
});
} catch (busiError) {
console.log("ndefFormatable formatReadOnly Promise catch busiError: " + busiError);
}
```
### NdefFormatableTag.formatReadOnly9+
formatReadOnly(message: [NdefMessage](#ndefmessage9), callback: AsyncCallback\): void
Formats this tag as an NDEF tag, writes an NDEF message to the NDEF tag, and then sets the tag to read-only. This API uses an asynchronous callback to return the result.
**Required permissions**: ohos.permission.NFC_TAG
**System capability**: SystemCapability.Communication.NFC.Tag
**Parameters**
| Name | Type | Mandatory| Description |
| -------- | ----------------------- | ---- | -------------------------------------- |
| message | [NdefMessage](#ndefmessage9) | Yes | NDEF message to write. If this parameter is **null**, the tag is formatted only (no data will be written).|
**Return value**
| **Type**| **Description** |
| ------------------ | --------------------------|
| callback: AsyncCallback\ | Callback invoked to return the result.|
**Example**
```js
import tag from '@ohos.nfc.tag';
// Check whether 'tag.TagInfo' in 'js-apis-nfcTag.md' has obtained 'ndefFormatable' correctly.
// Connect to the tag if it is not connected.
if (!ndefFormatable.isTagConnected()) {
if (!ndefFormatable.connectTag()) {
console.log("ndefFormatable connectTag failed.");
return;
}
}
try {
// NDEF message created from raw data, such as:
let ndefMessage = tag.ndef.createNdefMessage([0xD1, 0x01, 0x03, 0x54, 0x4E, 0x46, 0x43]); // It must be parsed as NDEF Record.
// or ndefMessage created from tag.ndef.createNdefMessage(ndefRecords: NdefRecord[])
ndefFormatable.formatReadOnly(ndefMessage, (err)=> {
if (err) {
console.log("ndefFormatable formatReadOnly AsyncCallback err: " + err);
} else {
console.log("ndefFormatable formatReadOnly AsyncCallback success.");
}
});
} catch (busiError) {
console.log("ndefFormatable formatReadOnly AsyncCallback catch busiError: " + busiError);
}
```