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Signed-off-by: NAnnie_wang <annie.wangli@huawei.com>
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en/application-dev/reference/apis/Readme-EN.md
浏览文件 @ c39559ec
......@@ -325,7 +325,7 @@
- [@ohos.enterprise.dateTimeManager](js-apis-enterprise-dateTimeManager.md)
- Language Base Class Library
- [@ohos.buffer](js-apis-buffer.md)
- [@ohos.buffer (Buffer)](js-apis-buffer.md)
- [@ohos.convertxml](js-apis-convertxml.md)
- [@ohos.process](js-apis-process.md)
- [@ohos.uri](js-apis-uri.md)
......
en/application-dev/reference/apis/js-apis-buffer.md
浏览文件 @ c39559ec
# Buffer
# @ohos.buffer (Buffer)
> **NOTE**
> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.
A **Buffer** object represents a byte sequence of a fixed length. It is used to store binary data.
A **Buffer** object represents a fixed-length sequence of bytes. It is used to store binary data.
You can use the APIs provided by the Buffer module to process images and a large amount of binary data, and receive or upload files.
You can use the APIs provided by the **Buffer** module to process images and a large amount of binary data, and receive or upload files.
> **NOTE**
>
> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.
## Modules to Import
......@@ -21,55 +22,23 @@ Enumerates the supported encoding formats of strings.
| Encoding Format | Description |
| ------- | -------------------- |
| ascii | ASCII format. |
| utf8 | UTF-8 |
| utf-8 | UTF-8 format.|
| utf16le | UTF-16LE format.|
| ucs2 | UTF-16LE format.|
| ucs-2 | UTF-16LE format.|
| base64 | Base64 format.|
| base64url | Base64 format.|
| latin1 | ASCII format.|
| binary | Binary format.|
| hex | Hexadecimal format.|
## Buffer
### Attributes
**System capability**: SystemCapability.Utils.Lang
| Name| Type| Readable| Writable| Description|
| -------- | -------- | -------- | -------- | -------- |
| length | number | Yes| No| Length of the buffer, in bytes.|
| buffer | ArrayBuffer | Yes| No| **ArrayBuffer** object.|
| byteOffset | number | Yes| No| Offset of the buffer in the memory pool.|
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
| ID| Error Message|
| -------- | -------- |
| 10200013 | Cannot set property ${propertyName} of Buffer which has only a getter. |
**Example**
```ts
import buffer from '@ohos.buffer';
let buf = buffer.from("1236");
console.log(JSON.stringify(buf.length));
let arrayBuffer = buf.buffer;
console.log(JSON.stringify(new Uint8Array(arrayBuffer)));
console.log(JSON.stringify(buf.byteOffset));
```
### alloc
| 'ascii' | ASCII format, which is case insensitive.|
| 'utf8' | UTF-8 format, which is case insensitive.|
| 'utf-8' | UTF-8 format, which is case insensitive.|
| 'utf16le' | UTF-16 little-endian format, which is case insensitive.|
| 'ucs2' | UTF-16 little-endian format, which is case insensitive.|
| 'ucs-2' | UTF-16 little-endian format, which is case insensitive.|
| 'base64' | Base64 format, which is case insensitive.|
| 'base64url' | Base64 format, which is case insensitive.|
| 'latin1' | ASCII format, which is case insensitive.|
| 'binary' | Binary format, which is case insensitive.|
| 'hex' | Hexadecimal format, which is case insensitive.|
## buffer.alloc
alloc(size: number, fill?: string | Buffer | number, encoding?: BufferEncoding): Buffer
Allocates and initializes a **Buffer** instance of the specified size.
Creates and initializes a **Buffer** instance of the specified length.
**System capability**: SystemCapability.Utils.Lang
......@@ -77,8 +46,8 @@ Allocates and initializes a **Buffer** instance of the specified size.
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| size | number | Yes| Size of the **Buffer** instance to allocate, in bytes.|
| fill | string&nbsp;\|&nbsp;Buffer&nbsp;\|&nbsp;number | No| Pre-filled value. The default value is **0**.|
| size | number | Yes| Size of the **Buffer** instance to create, in bytes.|
| fill | string&nbsp;\|&nbsp;Buffer&nbsp;\|&nbsp;number | No| Value to be filled in the buffer. The default value is **0**.|
| encoding | [BufferEncoding](#bufferencoding) | No| Encoding format (valid only when **fill** is a string). The default value is **utf-8**.|
**Return value**
......@@ -97,12 +66,12 @@ let buf2 = buffer.alloc(5, 'a');
let buf3 = buffer.alloc(11, 'aGVsbG8gd29ybGQ=', 'base64');
```
### allocUninitializedFromPool
## buffer.allocUninitializedFromPool
allocUninitializedFromPool(size: number): Buffer
Allocates a **Buffer** instance of the specified size from the buffer pool, without initializing it.
To initialize the **Buffer** instance, call **fill()**.
Creates a **Buffer** instance of the specified size from the buffer pool, without initializing it.
You need to use [fill()](#fill) to initialize the **Buffer** instance created.
**System capability**: SystemCapability.Utils.Lang
......@@ -110,7 +79,7 @@ To initialize the **Buffer** instance, call **fill()**.
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| size | number | Yes| Size of the **Buffer** instance to allocate, in bytes.|
| size | number | Yes| Size of the **Buffer** instance to create, in bytes.|
**Return value**
......@@ -127,11 +96,12 @@ let buf = buffer.allocUninitializedFromPool(10);
buf.fill(0);
```
### allocUninitialized
## buffer.allocUninitialized
allocUninitialized(size: number): Buffer
Allocates a **Buffer** instance of the specified size, without initializing it. This API does not allocate memory from the buffer pool.
Creates a **Buffer** instance of the specified size, without initializing it. This API does not allocate memory from the buffer pool.
You need to use [fill()](#fill) to initialize the **Buffer** instance created.
**System capability**: SystemCapability.Utils.Lang
......@@ -139,7 +109,7 @@ Allocates a **Buffer** instance of the specified size, without initializing it.
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| size | number | Yes|Size of the **Buffer** instance to allocate, in bytes.|
| size | number | Yes|Size of the **Buffer** instance to create, in bytes.|
**Return value**
......@@ -156,7 +126,7 @@ let buf = buffer.allocUninitialized(10);
buf.fill(0);
```
### byteLength
## buffer.byteLength
byteLength(string: string | Buffer | TypedArray | DataView | ArrayBuffer | SharedArrayBuffer, encoding?: BufferEncoding): number
......@@ -169,7 +139,7 @@ Obtains the number of bytes of a string based on the encoding format.
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| string | string&nbsp;\|&nbsp;Buffer&nbsp;\|&nbsp;TypedArray&nbsp;\|&nbsp;DataView&nbsp;\|&nbsp;ArrayBuffer&nbsp;\|&nbsp;SharedArrayBuffer | Yes| Target string.|
| encoding | [BufferEncoding](#bufferencoding) | No| Encoding format. The default value is **utf-8**.|
| encoding | [BufferEncoding](#bufferencoding) | No| Encoding format of the string. The default value is **utf-8**.|
**Return value**
......@@ -187,7 +157,7 @@ console.log(`${str}: ${str.length} characters, ${buffer.byteLength(str, 'utf-8')
// Print: ½ + ¼ = ¾: 9 characters, 12 bytes
```
### compare
## buffer.compare
compare(buf1: Buffer | Uint8Array, buf2: Buffer | Uint8Array): -1 | 0 | 1
......@@ -221,11 +191,11 @@ let res = buf1.compare(buf2);
console.log(Number(res).toString()); // Print 1.
```
### concat
## buffer.concat
concat(list: Buffer[] | Uint8Array[], totalLength?: number): Buffer
Concatenates an array of **Buffer** instances into a new instance of the specified length.
Concatenates an array of **Buffer** instances of the specified length into a new instance.
**System capability**: SystemCapability.Utils.Lang
......@@ -234,7 +204,7 @@ Concatenates an array of **Buffer** instances into a new instance of the specifi
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| list | Buffer[]&nbsp;\|&nbsp;Uint8Array[] | Yes| Array of instances to concatenate.|
| totalLength | number | No| Total length of the new **Buffer** instance, in bytes.|
| totalLength | number | No| Total length of bytes to be copied.|
**Return value**
......@@ -244,7 +214,7 @@ Concatenates an array of **Buffer** instances into a new instance of the specifi
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -261,7 +231,7 @@ let buf = buffer.concat([buf1, buf2]);
console.log(buf.toString('hex')); // 3132333461626364
```
### from
## buffer.from
from(array: number[]): Buffer;
......@@ -290,11 +260,11 @@ let buf = buffer.from([0x62, 0x75, 0x66, 0x66, 0x65, 0x72]);
console.log(buf.toString('hex')); // 627566666572
```
### from
## buffer.from
from(arrayBuffer: ArrayBuffer | SharedArrayBuffer, byteOffset?: number, length?: number): Buffer
Creates a **Buffer** instance that shares memory with the specified array of **Buffer** instances.
Creates a **Buffer** instance of the specified length that shares memory with **arrayBuffer**.
**System capability**: SystemCapability.Utils.Lang
......@@ -314,7 +284,7 @@ Creates a **Buffer** instance that shares memory with the specified array of **B
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -329,7 +299,7 @@ let ab = new ArrayBuffer(10);
let buf = buffer.from(ab, 0, 2);
```
### from
## buffer.from
from(buffer: Buffer | Uint8Array): Buffer
......@@ -341,7 +311,7 @@ Creates a **Buffer** instance with the copy of another instance.
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| buffer | Buffer&nbsp;\|&nbsp;Uint8Array | Yes| **Buffer** instance to copy. |
| buffer | Buffer&nbsp;\|&nbsp;Uint8Array | Yes| **Buffer** instance to copy.|
**Return value**
......@@ -358,7 +328,7 @@ let buf1 = buffer.from('buffer');
let buf2 = buffer.from(buf1);
```
### from
## buffer.from
from(object: Object, offsetOrEncoding: number | string, length: number): Buffer
......@@ -385,10 +355,10 @@ Creates a **Buffer** instance based on the specified object.
```ts
import buffer from '@ohos.buffer';
let buf = buffer.from(new String('this is a test'));
let buf = buffer.from(new String('this is a test'), 'utf8', 14);
```
### from
## buffer.from
from(string: String, encoding?: BufferEncoding): Buffer
......@@ -418,11 +388,11 @@ let buf1 = buffer.from('this is a test');
let buf2 = buffer.from('7468697320697320612074c3a97374', 'hex');
console.log (buf1.toString()); // Print: this is a test
console.log(buf2.toString());
console.log (buf2.toString()); // print: this is a test
```
### isBuffer
## buffer.isBuffer
isBuffer(obj: Object): boolean
......@@ -454,7 +424,7 @@ buffer.isBuffer([]); // false
buffer.isBuffer(new Uint8Array(1024)); // false
```
### isEncoding
## buffer.isEncoding
isEncoding(encoding: string): boolean
......@@ -485,6 +455,70 @@ console.log(buffer.isEncoding('utf/8').toString()); // Print: false
console.log(buffer.isEncoding('').toString()); // Print: false
```
## buffer.transcode
transcode(source: Buffer | Uint8Array, fromEnc: string, toEnc: string): Buffer
Transcodes the given **Buffer** or **Uint8Array** object from one encoding format to another.
**System capability**: SystemCapability.Utils.Lang
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| source | Buffer&nbsp;\|&nbsp;Uint8Array | Yes| Instance to encode.|
| fromEnc | string | Yes| Current encoding format.|
| toEnc | string | Yes| Target encoding format.|
**Return value**
| Type| Description|
| -------- | -------- |
| Buffer | New **Buffer** instance in the target encoding format.|
**Example**
```ts
import buffer from '@ohos.buffer';
let buf = buffer.alloc(50);
let newBuf = buffer.transcode(buffer.from('€'), 'utf-8', 'ascii');
console.log(newBuf.toString('ascii'));
```
## Buffer
### Attributes
**System capability**: SystemCapability.Utils.Lang
| Name| Type| Readable| Writable| Description|
| -------- | -------- | -------- | -------- | -------- |
| length | number | Yes| No| Length of the **Buffer** instance, in bytes.|
| buffer | ArrayBuffer | Yes| No| **ArrayBuffer** object.|
| byteOffset | number | Yes| No| Offset of the **Buffer** instance in the memory pool.|
**Error codes**
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
| 10200013 | Cannot set property ${propertyName} of Buffer which has only a getter. |
**Example**
```ts
import buffer from '@ohos.buffer';
let buf = buffer.from("1236");
console.log(JSON.stringify(buf.length));
let arrayBuffer = buf.buffer;
console.log(JSON.stringify(new Uint8Array(arrayBuffer)));
console.log(JSON.stringify(buf.byteOffset));
```
### compare
compare(target: Buffer | Uint8Array, targetStart?: number, targetEnd?: number, sourceStart?: number, sourceEnd?: number): -1 | 0 | 1
......@@ -507,7 +541,15 @@ Compares this **Buffer** instance with another instance.
| Type| Description|
| -------- | -------- |
| number | Returns **0** if the two **Buffer** instances are the same.<br>Returns **1** if this instance comes after the target instance when sorted.<br>Returns **-1** if this instance comes before the target instance when sorted. |
| number | Returns **0** if the two **Buffer** instances are the same.<br>Returns **1** if this instance comes after the target instance when sorted. <br>Returns **-1** if this instance comes before the target instance when sorted.|
**Error codes**
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
| 10200001 | The value of "[targetStart/targetEnd/sourceStart/sourceEnd]" is out of range. |
**Example**
......@@ -547,7 +589,7 @@ Copies data at the specified position in this **Buffer** instance to the specifi
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -578,6 +620,13 @@ Creates and returns an iterator that contains key-value pairs of this **Buffer**
**System capability**: SystemCapability.Utils.Lang
**Return value**
| Type| Description|
| -------- | -------- |
| number | Key of the iterator.|
| number | Value of the iterator.|
**Example**
```ts
......@@ -647,7 +696,7 @@ Fills this **Buffer** instance at the specified position. By default, data is fi
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -739,7 +788,7 @@ Creates and returns an iterator that contains the keys of this **Buffer** instan
| Type| Description|
| -------- | -------- |
| IterableIterator&lt;number&gt; | Iterator.|
| IterableIterator&lt;number&gt; | Iterator created.|
**Example**
......@@ -789,7 +838,7 @@ console.log(buf.lastIndexOf('buffer').toString()); // Print: 17
readBigInt64BE(offset?: number): bigint
Reads a signed, big-endian 64-bit Big integer from this **Buffer** instance at the specified offset.
Reads a signed, big-endian 64-bit integer from this **Buffer** instance at the specified offset.
**System capability**: SystemCapability.Utils.Lang
......@@ -807,7 +856,7 @@ Reads a signed, big-endian 64-bit Big integer from this **Buffer** instance at t
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -848,7 +897,7 @@ Reads a signed, little-endian 64-bit Big integer from this **Buffer** instance a
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -889,7 +938,7 @@ Reads an unsigned, big-endian 64-bit Big integer from this **Buffer** instance a
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -930,7 +979,7 @@ Reads an unsigned, little-endian 64-bit Big integer from this **Buffer** instanc
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -971,7 +1020,7 @@ Reads a big-endian double-precision floating-point number from this **Buffer** i
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1011,7 +1060,7 @@ Reads a little-endian double-precision floating-point number from this **Buffer*
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1051,7 +1100,7 @@ Reads a big-endian single-precision floating-point number from this **Buffer** i
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1091,7 +1140,7 @@ Reads a little-endian single-precision floating-point number from this **Buffer*
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1131,7 +1180,7 @@ Reads a signed 8-bit integer from this **Buffer** instance at the specified offs
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1172,7 +1221,7 @@ Reads a signed, big-endian 16-bit integer from this **Buffer** instance at the s
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1212,7 +1261,7 @@ Reads a signed, little-endian 16-bit integer from this **Buffer** instance at th
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1252,7 +1301,7 @@ Reads a signed, big-endian 32-bit integer from this **Buffer** instance at the s
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1292,7 +1341,7 @@ Reads a signed, little-endian 32-bit integer from this **Buffer** instance at th
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1334,7 +1383,7 @@ Reads the specified number of bytes from this **Buffer** instance at the specifi
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1378,7 +1427,7 @@ Reads the specified number of bytes from this **Buffer** instance at the specifi
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1419,7 +1468,7 @@ Reads an unsigned 8-bit integer from this **Buffer** instance at the specified o
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1461,7 +1510,7 @@ Reads an unsigned, big-endian 16-bit integer from this **Buffer** instance at th
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1503,7 +1552,7 @@ Reads an unsigned, little-endian 16-bit integer from this **Buffer** instance at
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1545,7 +1594,7 @@ Reads an unsigned, big-endian 32-bit integer from this **Buffer** instance at th
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1586,7 +1635,7 @@ Reads an unsigned, little-endian 32-bit integer from this **Buffer** instance at
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1628,7 +1677,7 @@ Reads the specified number of bytes from this **Buffer** instance at the specifi
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1670,7 +1719,7 @@ Reads the specified number of bytes from this **Buffer** instance at the specifi
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1741,7 +1790,7 @@ Interprets this **Buffer** instance as an array of unsigned 16-bit integers and
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1776,7 +1825,7 @@ Interprets this **Buffer** instance as an array of unsigned 32-bit integers and
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1811,7 +1860,7 @@ Interprets this **Buffer** instance as an array of unsigned 64-bit integers and
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1901,7 +1950,7 @@ Creates and returns an iterator that contains the values of this **Buffer** inst
| Type| Description|
| -------- | -------- |
| IterableIterator&lt;number&gt; | Iterator created.|
| IterableIterator&lt;number&gt; | Iterator.|
**Example**
......@@ -1940,7 +1989,7 @@ Writes a string of the specified length to this **Buffer** instance at the speci
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -1984,7 +2033,7 @@ Writes a signed, big-endian 64-bit Big integer to this **Buffer** instance at th
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2023,7 +2072,7 @@ Writes a signed, little-endian 64-bit Big integer to this **Buffer** instance at
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2062,7 +2111,7 @@ Writes an unsigned, big-endian 64-bit Big integer to this **Buffer** instance at
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2101,7 +2150,7 @@ Writes an unsigned, little-endian 64-bit Big integer to this **Buffer** instance
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2140,7 +2189,7 @@ Writes a big-endian double-precision floating-point number to this **Buffer** in
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2179,7 +2228,7 @@ Writes a little-endian double-precision floating-point number to this **Buffer**
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2218,7 +2267,7 @@ Writes a big-endian single-precision floating-point number to this **Buffer** in
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2258,7 +2307,7 @@ Writes a little-endian single-precision floating-point number to this **Buffer**
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2297,7 +2346,7 @@ Writes a signed 8-bit integer to this **Buffer** instance at the specified offse
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2338,7 +2387,7 @@ Writes a signed, big-endian 16-bit integer to this **Buffer** instance at the sp
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2378,7 +2427,7 @@ Writes a signed, little-endian 16-bit integer to this **Buffer** instance at the
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2417,7 +2466,7 @@ Writes a signed, big-endian 32-bit integer to this **Buffer** instance at the sp
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2457,7 +2506,7 @@ Writes a signed, little-endian 32-bit integer to this **Buffer** instance at the
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2497,7 +2546,7 @@ Writes a big-endian signed value of the specified length to this **Buffer** inst
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2538,7 +2587,7 @@ Writes a little-endian signed value of the specified length to this **Buffer** i
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2577,7 +2626,7 @@ Writes an unsigned 8-bit integer to this **Buffer** instance at the specified of
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2619,7 +2668,7 @@ Writes an unsigned, big-endian 16-bit integer to this **Buffer** instance at the
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2659,7 +2708,7 @@ Writes an unsigned, little-endian 16-bit integer to this **Buffer** instance at
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2699,7 +2748,7 @@ Writes an unsigned, big-endian 32-bit integer to this **Buffer** instance at the
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2738,7 +2787,7 @@ Writes an unsigned, little-endian 32-bit integer to this **Buffer** instance at
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2778,7 +2827,7 @@ Writes an unsigned big-endian value of the specified length to this **Buffer** i
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2818,7 +2867,7 @@ Writes an unsigned little-endian value of the specified length to this **Buffer*
**Error codes**
For details about the error codes, see [Buffer Error Codes](../errorcodes/errorcode-buffer.md).
For details about the error codes, see [Utils Error Codes](../errorcodes/errorcode-utils.md).
| ID| Error Message|
| -------- | -------- |
......@@ -2833,38 +2882,6 @@ let buf = buffer.allocUninitializedFromPool(6);
buf.writeUIntLE(0x1234567890ab, 0, 6);
```
### transcode
transcode(source: Buffer | Uint8Array, fromEnc: string, toEnc: string): Buffer
Transcodes the given **Buffer** or **Uint8Array** instance from one encoding format to another.
**System capability**: SystemCapability.Utils.Lang
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| source | Buffer&nbsp;\|&nbsp;Uint8Array | Yes| Instance to transcode. |
| fromEnc | string | Yes| Current encoding format.|
| toEnc | string | Yes| Target encoding format.|
**Return value**
| Type| Description|
| -------- | -------- |
| Buffer | New **Buffer** instance in the target encoding format.|
**Example**
```ts
import buffer from '@ohos.buffer';
let buf = buffer.alloc(50);
let newBuf = buffer.transcode(buffer.from('€'), 'utf-8', 'ascii');
console.log(newBuf.toString('ascii'));
```
## Blob
### Attributes
......@@ -2941,7 +2958,7 @@ Creates a **Blob** instance by copying specified data from this **Blob** instanc
**Return value**
| Type| Description|
| -------- | -------- |
| Blob | **Blob** instance created. |
| Blob | New **Blob** instance created.|
**Example**
```ts
......@@ -2954,7 +2971,7 @@ let blob3 = blob.slice(0, 2, "MIME");
text(): Promise&lt;string&gt;
Returns text in UTF-8 format.
Returns text in UTF-8 format. This API uses a promise to return the result.
**System capability**: SystemCapability.Utils.Lang
......
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