diff --git a/en/application-dev/reference/apis/Readme-EN.md b/en/application-dev/reference/apis/Readme-EN.md index 7ec2ef1b9e52f9d3e4e53a0caa9bcfd5a9498c9f..1cb11c65570db521c8f311ecac3ced3177e5bfac 100644 --- a/en/application-dev/reference/apis/Readme-EN.md +++ b/en/application-dev/reference/apis/Readme-EN.md @@ -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) diff --git a/en/application-dev/reference/apis/js-apis-buffer.md b/en/application-dev/reference/apis/js-apis-buffer.md index b5c914e7725c878305ff0235a33d8d98d6c6d6e4..72e65e53e63380ef4ea0aa9b33796e236bc7ee84 100644 --- a/en/application-dev/reference/apis/js-apis-buffer.md +++ b/en/application-dev/reference/apis/js-apis-buffer.md @@ -1,11 +1,12 @@ -# 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 \| Buffer \| number | No| Pre-filled value. The default value is **0**.| +| size | number | Yes| Size of the **Buffer** instance to create, in bytes.| +| fill | string \| Buffer \| 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 \| Buffer \| TypedArray \| DataView \| ArrayBuffer \| 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[] \| 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 \| Uint8Array | Yes| **Buffer** instance to copy. | +| buffer | Buffer \| 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 \| 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.
Returns **1** if this instance comes after the target instance when sorted.
Returns **-1** if this instance comes before the target instance when sorted. | +| number | Returns **0** if the two **Buffer** instances are the same.
Returns **1** if this instance comes after the target instance when sorted.
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<number> | Iterator.| +| IterableIterator<number> | 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<number> | Iterator created.| +| IterableIterator<number> | 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 \| 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<string> -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