File API

https://www.w3.org/TR/FileAPI/
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File API provides standard web interfaces for representing file objects in web applications and...
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### Blob() Constructor

Source: https://www.w3.org/TR/FileAPI

Documentation for the Blob constructor, including its parameters and usage examples.

```APIDOC
## [Constructor] Blob()

### Description
Creates a new Blob object. The constructor can accept an optional array of BlobPart values (ArrayBuffer, ArrayBufferView, Blob, or DOMString) and an optional options object with a type property.

### Method
Constructor

### Parameters
#### Request Body
- **blobParts** (Array<BlobPart>) - Optional - An array of BlobPart values (ArrayBuffer, ArrayBufferView, Blob, or DOMString) to be included in the Blob.
- **options** (BlobPropertyBag) - Optional - An object with a `type` property (DOMString) specifying the media type of the Blob.

### Request Example
```js
// Create a new Blob object
var a = new Blob();

// Create a 1024-byte ArrayBuffer
var buffer = new ArrayBuffer(1024);

// Create ArrayBufferView objects based on buffer
var shorts = new Uint16Array(buffer, 512, 128);
var bytes = new Uint8Array(buffer, shorts.byteOffset + shorts.byteLength);

var b = new Blob(["foobarbazetcetc" + "birdiebirdieboo"], {type: "text/plain;charset=utf-8"});

var c = new Blob([b, shorts]);

var a = new Blob([b, c, bytes]);

var d = new Blob([buffer, b, c, bytes]);
```

### Response
#### Success Response
Returns a new Blob object.

```

--------------------------------

### FileReader example: read file as UTF-16 with progress and error handling

Source: https://www.w3.org/TR/FileAPI

Example from the File API introduction showing how to read a file asynchronously using FileReader. It includes functions for starting the read, handling progress, success, and errors. The example uses readAsText with UTF-16 encoding and checks for NotReadableError.

```javascript
function startRead() {
  // obtain input element through DOM

  var file = document.getElementById('file').files[0];
  if(file){
    getAsText(file);
  }
}

function getAsText(readFile) {

  var reader = new FileReader();

  // Read file into memory as UTF-16
  reader.readAsText(readFile, "UTF-16");

  // Handle progress, success, and errors
  reader.onprogress = updateProgress;
  reader.onload = loaded;
  reader.onerror = errorHandler;
}

function updateProgress(evt) {
  if (evt.lengthComputable) {
    // evt.loaded and evt.total are ProgressEvent properties
    var loaded = (evt.loaded / evt.total);
    if (loaded < 1) {
      // Increase the prog bar length
      // style.width = (loaded * 200) + "px";
    }
  }
}

function loaded(evt) {
  // Obtain the read file data
  var fileString = evt.target.result;
  // Handle UTF-16 file dump
  if(utils.regexp.isChinese(fileString)) {
    //Chinese Characters + Name validation
  }
  else {
    // run other charset test
  }
  // xhr.send(fileString)
}

function errorHandler(evt) {
  if(evt.target.error.name == "NotReadableError") {
    // The file could not be read
  }
}
```

--------------------------------

### Access selected files from an input element

Source: https://www.w3.org/TR/FileAPI

JavaScript example showing how to access the first selected file from an <input type="file"> element via a form. Includes an alternative syntax using item(0) and a check before performing file operations.

```javascript
// uploadData is a form element
// fileChooser is input element of type 'file'
var file = document.forms['uploadData']['fileChooser'].files[0];

// alternative syntax can be
// var file = document.forms['uploadData']['fileChooser'].files.item(0);

if(file)
{
  // Perform file ops
}
```

--------------------------------

### FileReader.readAsBinaryString(blob)

Source: https://www.w3.org/TR/FileAPI

Starts reading the contents of the specified Blob as a binary string.

```APIDOC
## FileReader.readAsBinaryString(blob)

### Description
Starts reading the contents of the specified Blob as a binary string. The result will be available in the result attribute after the read completes.

### Method
readAsBinaryString(blob)

### Parameters
- **blob** (Blob) - Required - The Blob or File to read.

### Example
js
reader.readAsBinaryString(file);

```

--------------------------------

### Create and revoke a blob URL across windows

Source: https://www.w3.org/TR/FileAPI

Shows creating a blob URL in one window and revoking it in another window of the same origin. The example assumes window2 could be an iframe inside window1.

```javascript
myurl = window1.URL.createObjectURL(myblob);
window2.URL.revokeObjectURL(myurl);

```

--------------------------------

### FileReader.readAsText(blob, encoding)

Source: https://www.w3.org/TR/FileAPI

Starts reading the contents of the specified Blob as text using the given encoding.

```APIDOC
## FileReader.readAsText(blob, encoding)

### Description
Starts reading the contents of the specified Blob as text. The encoding parameter is optional and specifies the character encoding to use.

### Method
readAsText(blob, encoding)

### Parameters
- **blob** (Blob) - Required - The Blob or File to read.
- **encoding** (DOMString) - Optional - The character encoding to use for decoding the text.

### Example
js
reader.readAsText(file, 'UTF-8');

```

--------------------------------

### FileReader.readAsArrayBuffer(blob)

Source: https://www.w3.org/TR/FileAPI

Starts reading the contents of the specified Blob as an ArrayBuffer.

```APIDOC
## FileReader.readAsArrayBuffer(blob)

### Description
Starts reading the contents of the specified Blob as an ArrayBuffer. The result will be available in the result attribute after the read completes.

### Method
readAsArrayBuffer(blob)

### Parameters
- **blob** (Blob) - Required - The Blob or File to read.

### Example
js
reader.readAsArrayBuffer(file);

```

--------------------------------

### FileReader.readAsDataURL(blob)

Source: https://www.w3.org/TR/FileAPI

Starts reading the contents of the specified Blob as a data URL.

```APIDOC
## FileReader.readAsDataURL(blob)

### Description
Starts reading the contents of the specified Blob as a data URL. The result will be available in the result attribute after the read completes.

### Method
readAsDataURL(blob)

### Parameters
- **blob** (Blob) - Required - The Blob or File to read.

### Example
js
reader.readAsDataURL(file);

```

--------------------------------

### File Interface

Source: https://www.w3.org/TR/FileAPI

Documentation for the File interface constructor and its attributes.

```APIDOC
## [Constructor] File()

### Description
Creates a new File object from the provided file bits, file name, and optional properties.

### Method
Constructor

### Parameters
#### fileBits (sequence)
- Required - A sequence of BufferSource, Blob, or USVString elements.

#### fileName (USVString)
- Required - The name of the file.

#### options (FilePropertyBag)
- Optional - A dictionary that may include a `lastModified` member (long long).

### Request Example
```js
var file = new File(["content"], "example.txt", {lastModified: 1234567890});
```

### Response
#### Success Response
Returns a new File object with the specified name, type, size, and lastModified attributes.
```

```APIDOC
## [Attribute] File.name

### Description
Returns the name of the file as a string, without path information.

### Method
Attribute (readonly)

### Response
#### Success Response
Returns a DOMString representing the file name.
```

```APIDOC
## [Attribute] File.lastModified

### Description
Returns the last modified date of the file as the number of milliseconds since the Unix Epoch.

### Method
Attribute (readonly)

### Response
#### Success Response
Returns a long long representing the last modified time in milliseconds.
```

--------------------------------

### File constructor

Source: https://www.w3.org/TR/FileAPI

Creates a new File object, which is a Blob with a name and last modified date.

```APIDOC
## File Constructor

### Description
Creates a new File object, which is a Blob with a name and last modified date.

### Method
Constructor

### Parameters
- **fileBits** (sequence<BlobPart>) - Required - The parts to concatenate into the File.
- **fileName** (USVString) - Required - The name of the file.
- **options** (FilePropertyBag) - Optional - An object with properties `type`, `endings`, and `lastModified` (long long).

### Returns
A new File object.
```

--------------------------------

### FileReader.readyState

Source: https://www.w3.org/TR/FileAPI

Read-only attribute that returns the current state of the FileReader.

```APIDOC
## FileReader.readyState

### Description
Returns the current state of the FileReader (EMPTY, LOADING, or DONE).

### Property
readonly attribute unsigned short readyState

### Constants
- EMPTY = 0
- LOADING = 1
- DONE = 2

### Returns
unsigned short - The current state.
```

--------------------------------

### FileReader.readyState

Source: https://www.w3.org/TR/FileAPI

Returns the current state of the FileReader as one of the constants EMPTY, LOADING, or DONE.

```APIDOC
## FileReader.readyState

### Description
Returns the current state of the FileReader. The value is one of the constants EMPTY (0), LOADING (1), or DONE (2).

### Attribute
- **readyState** (unsigned short) - readonly - The current state of the reader.

### Example
js
if (reader.readyState === FileReader.DONE) { ... }

```

--------------------------------

### Blob() Constructor

Source: https://www.w3.org/TR/FileAPI

Creates a new Blob object. Can be invoked with zero or more parameters. When invoked with zero parameters, returns an empty Blob. Otherwise, processes the provided blob parts and options to create a Blob with the specified data and type.

```APIDOC
## Blob() Constructor

### Description
Creates a new Blob object. Can be invoked with zero or more parameters. When invoked with zero parameters, returns an empty Blob. Otherwise, processes the provided blob parts and options to create a Blob with the specified data and type.

### Method
Constructor

### Endpoint
Blob()

### Parameters
#### Constructor Parameters
- **blobParts** (sequence) - Optional - A sequence of elements, each of which can be a BufferSource, Blob, or USVString.
- **options** (BlobPropertyBag) - Optional - An object with optional members:
  - **type** (string) - Optional - The ASCII-encoded string in lower case representing the media type of the Blob.
  - **endings** (enum) - Optional - Can be "transparent" or "native". Default is "transparent". If "native", line endings in USVString elements are converted to native.

### Request Example
```
new Blob(["Hello, world!"], { type: "text/plain" });
```

### Response
#### Success Response
Returns a new Blob object with the specified byte sequence, size, and type.

#### Response Example
```
Blob { size: 13, type: "text/plain" }
```
```

--------------------------------

### Blob()

Source: https://www.w3.org/TR/FileAPI

Constructor for creating a new Blob object from a sequence of BlobParts and an optional BlobPropertyBag.

```APIDOC
## [CONSTRUCTOR] Blob()

### Description
Creates a new Blob object from a sequence of BlobParts and an optional BlobPropertyBag.

### Method
Constructor

### Endpoint
Blob(optional sequence<BlobPart> blobParts, optional BlobPropertyBag options = {})

### Parameters
#### Constructor Parameters
- **blobParts** (sequence<BlobPart>) - Optional - A sequence of BlobPart items (BufferSource, Blob, or USVString) to concatenate into the Blob.
- **options** (BlobPropertyBag) - Optional - A dictionary with `type` (DOMString, default "") and `endings` (EndingType, default "transparent").

### Request Example
```js
const blob = new Blob(["Hello, world!"], { type: "text/plain" });
```

### Response
#### Success Response
- **blob** (Blob) - The newly created Blob object.

#### Response Example
```js
Blob { size: 13, type: "text/plain" }
```
```

--------------------------------

### File constructor

Source: https://www.w3.org/TR/FileAPI

The File constructor creates a new File object from a sequence of BlobParts and a file name.

```APIDOC
## [File constructor]

### Description
The `File` constructor creates a new `File` object from a sequence of `BlobPart` and a file name.

### Method
constructor

### Endpoint
new File(fileBits, fileName, options)

### Parameters
#### Path Parameters
- **fileBits** (sequence<BlobPart>) - Required - The parts to include in the file.
- **fileName** (USVString) - Required - The name of the file.
- **options** (FilePropertyBag) - Optional - Additional options, including `lastModified`.

### Response
#### Success Response
Returns a new File object.
```

--------------------------------

### URL.createObjectURL()

Source: https://www.w3.org/TR/FileAPI

Creates a URL for the given Blob or MediaSource object.

```APIDOC
## URL.createObjectURL()

### Description
Creates a URL for the given Blob or MediaSource object.

### Method
static DOMString createObjectURL((Blob or MediaSource) obj)

### Parameters
- **obj** (Blob or MediaSource) - Required - The object to create a URL for.

### Returns
DOMString - The generated object URL.
```

--------------------------------

### FileReaderSync constructor

Source: https://www.w3.org/TR/FileAPI

Creates a new FileReaderSync object. When invoked, the user agent must return a new FileReaderSync object.

```APIDOC
## FileReaderSync()

### Description
Creates a new FileReaderSync object.

### Method
constructor

### Syntax
new FileReaderSync()

### Parameters
None.

### Return Value
A new FileReaderSync object.

### Exceptions
None.
```

--------------------------------

### FileReader constructor

Source: https://www.w3.org/TR/FileAPI

Creates a new FileReader object.

```APIDOC
## FileReader Constructor

### Description
Creates a new FileReader object for reading files asynchronously.

### Method
Constructor

### Returns
A new FileReader object.
```

--------------------------------

### FileReaderSync constructor

Source: https://www.w3.org/TR/FileAPI

Creates a new FileReaderSync object.

```APIDOC
## FileReaderSync Constructor

### Description
Creates a new FileReaderSync object for synchronous file reading in workers.

### Method
Constructor

### Returns
A new FileReaderSync object.
```

--------------------------------

### Blob constructor

Source: https://www.w3.org/TR/FileAPI

Creates a new Blob object from a sequence of BlobParts and an optional BlobPropertyBag.

```APIDOC
## Blob Constructor

### Description
Creates a new Blob object containing the concatenation of the given blob parts.

### Method
Constructor

### Parameters
- **blobParts** (sequence<BlobPart>) - Optional - The parts to concatenate into the Blob.
- **options** (BlobPropertyBag) - Optional - An object with properties `type` (DOMString, default "") and `endings` (EndingType, default "transparent").

### Returns
A new Blob object.

### Example
```js
const blob = new Blob(['hello'], {type: 'text/plain'});
```
```

--------------------------------

### Create a blob URL and assign to two img elements

Source: https://www.w3.org/TR/FileAPI

Creates a blob URL from a Blob object and assigns it to the src of two img elements. Both images reference the same blob URL.

```javascript
url = URL.createObjectURL(blob);
img1.src = url;
img2.src = url;
```

--------------------------------

### Create a File object with custom lastModified date

Source: https://www.w3.org/TR/FileAPI

Shows how to construct a File object with a specified lastModified date using a Date object. The File constructor takes an array of data, a filename, and an options object with type and lastModified.

```javascript
var d = new Date(2013, 12, 5, 16, 23, 45, 600);
var generatedFile = new File(["Rough Draft ...."], "Draft1.txt", {type: "text/plain", lastModified: d})
```

--------------------------------

### Display file metadata and generate file with last modified date

Source: https://www.w3.org/TR/FileAPI

Displays metadata from a file selected via a file picker, including its name and last modified date, and includes a placeholder for generating a file with a specific last modified date.

```javascript
var file = document.getElementById("filePicker").files[0];
var date = new Date(file.lastModified);
println("You selected the file " + file.name + " which was modified on " + date.toDateString() + ".");

...

// Generate a file with a specific last modified date
```

--------------------------------

### URL interface for blob URL creation and revocation

Source: https://www.w3.org/TR/FileAPI

Defines the static methods for creating and revoking blob URLs. The createObjectURL method returns the result of adding an entry to the blob URL store, while revokeObjectURL silently fails if the URL is not registered or was created in a different storage partition.

```webidl
[Exposed=(Window,DedicatedWorker,SharedWorker)]
partial interface URL {
  static DOMString createObjectURL((Blob or MediaSource) obj);
  static undefined revokeObjectURL(DOMString url);
};

```

--------------------------------

### Blob.slice() Method

Source: https://www.w3.org/TR/FileAPI

Documentation for the Blob.slice() method, which creates a new Blob containing a subset of the original Blob's data.

```APIDOC
## [Method] Blob.slice()

### Description
The slice() method returns a new Blob object with bytes ranging from the optional start parameter up to but not including the optional end parameter, and with a type attribute that is the value of the optional contentType parameter.

### Method
slice

### Parameters
#### Query Parameters
- **start** (long long) - Optional - The start position of the slice. If omitted, the slice starts at the beginning.
- **end** (long long) - Optional - The end position of the slice (exclusive). If omitted, the slice extends to the end.
- **contentType** (DOMString) - Optional - The media type for the new Blob.

### Request Example
```js
// obtain input element through DOM
var file = document.getElementById('file').files[0];
if(file)
{
  // create an identical copy of file
  // the two calls below are equivalent
  var fileClone = file.slice();
  var fileClone2 = file.slice(0, file.size);

  // slice file into 1/2 chunk starting at middle of file
  // Note the use of negative number
  var fileChunkFromEnd = file.slice(-(Math.round(file.size/2)));

  // slice file into 1/2 chunk starting at beginning of file
  var fileChunkFromStart = file.slice(0, Math.round(file.size/2));

  // slice file from beginning till 150 bytes before end
  var fileNoMetadata = file.slice(0, -150, "application/experimental");
}
```

### Response
#### Success Response
Returns a new Blob object containing the specified byte range.

```

--------------------------------

### FileReader event handlers

Source: https://www.w3.org/TR/FileAPI

Event handler attributes for loadstart, progress, load, abort, error, and loadend events.

```APIDOC
## FileReader event handlers

### Description
These attributes allow setting event handlers for the FileReader's events: onloadstart, onprogress, onload, onabort, onerror, and onloadend.

### Attributes
- **onloadstart** (EventHandler) - Fired when reading starts.
- **onprogress** (EventHandler) - Fired during reading progress.
- **onload** (EventHandler) - Fired when reading successfully completes.
- **onabort** (EventHandler) - Fired when reading is aborted.
- **onerror** (EventHandler) - Fired when an error occurs.
- **onloadend** (EventHandler) - Fired when reading ends (success or failure).

### Example
js
reader.onload = function() { console.log(reader.result); };

```

--------------------------------

### URL.createObjectURL and URL.revokeObjectURL

Source: https://www.w3.org/TR/FileAPI

Static methods on the URL interface for creating and revoking blob URLs.

```APIDOC
## [STATIC] URL.createObjectURL(obj)

### Description
Creates a blob URL for the given Blob or MediaSource object and returns a DOMString that can be used to reference the object.

### Method
Static method on the URL interface.

### Endpoint
URL.createObjectURL(obj)

### Parameters
- **obj** (Blob or MediaSource) - Required - The object for which a blob URL is created.

### Returns
- **DOMString** - The generated blob URL.

### Example
```js
const url = URL.createObjectURL(blob);
```
```

```APIDOC
## [STATIC] URL.revokeObjectURL(url)

### Description
Revokes a previously created blob URL, decoupling it from the resource it refers to. After revocation, dereferencing the URL results in a network error.

### Method
Static method on the URL interface.

### Endpoint
URL.revokeObjectURL(url)

### Parameters
- **url** (DOMString) - Required - The blob URL to revoke.

### Behavior
- If the URL's scheme is not "blob", the method returns without action.
- If the URL is not registered or was created in a different storage partition, the revocation silently fails.
- Requests started before revocation should still succeed.

### Example
```js
URL.revokeObjectURL(url);
```
```

--------------------------------

### FileReader() constructor

Source: https://www.w3.org/TR/FileAPI

Creates a new FileReader object for reading file contents asynchronously.

```APIDOC
## FileReader() constructor

### Description
Constructs a new FileReader object. The object is initially in the EMPTY state with a null result and error.

### Method
constructor()

### Example
js
var reader = new FileReader();

```

--------------------------------

### createObjectURL(obj)

Source: https://www.w3.org/TR/FileAPI

Creates a blob URL for a Blob or File object.

```APIDOC
## createObjectURL(obj)

### Description
Creates a blob URL (also known as an object URL) for the given Blob or File object. The returned URL can be used to reference the object's data.

### Method
createObjectURL

### Parameters
- **obj** (Blob or File) - Required - The Blob or File object for which to create a blob URL.

### Returns
A string representing the generated blob URL.

```

--------------------------------

### readAsBinaryString(blob)

Source: https://www.w3.org/TR/FileAPI

Initiates an asynchronous read of a Blob or File, producing a binary string. Provided for backwards compatibility; prefer readAsArrayBuffer().

```APIDOC
## [FileReader] readAsBinaryString(blob)

### Description
Initiates a read operation for the given blob, producing a binary string.

### Method
readAsBinaryString

### Parameters
- **blob** (Blob) - Required - The blob to read.

### Response
Returns a binary string where each byte is represented by a code unit of equal value [0..255].
```

--------------------------------

### FileReader.readAsBinaryString()

Source: https://www.w3.org/TR/FileAPI

Asynchronously reads the Blob as a binary string.

```APIDOC
## FileReader.readAsBinaryString()

### Description
Starts reading the specified Blob as a binary string.

### Method
undefined readAsBinaryString(Blob blob)

### Parameters
- **blob** (Blob) - Required - The Blob to read.

### Returns
undefined
```

--------------------------------

### File.name

Source: https://www.w3.org/TR/FileAPI

The name attribute returns the name of the file.

```APIDOC
## [File.name]

### Description
The `name` attribute returns the name of the file.

### Method
attribute

### Endpoint
File.name

### Parameters
None.

### Response
#### Success Response
Returns a DOMString.
```

--------------------------------

### File Interface

Source: https://www.w3.org/TR/FileAPI

The File interface extends Blob and represents a file on the user's file system. It adds properties for name, last modified time, and relative path.

```APIDOC
## File Interface

### Description
The File interface represents a file on the user's file system. It inherits from Blob and adds file-specific attributes.

### Attributes
- `name` (DOMString) - The name of the file.
- `lastModified` (long long) - The last modified time of the file, in milliseconds since the Unix epoch.
- `webkitRelativePath` (DOMString) - The path of the file relative to the directory selected by the user.
```

--------------------------------

### FileList.item()

Source: https://www.w3.org/TR/FileAPI

Returns the File at the given index in the FileList.

```APIDOC
## FileList.item()

### Description
Returns the File object at the specified index in the FileList.

### Method
getter File? item(unsigned long index)

### Parameters
- **index** (unsigned long) - Required - The index of the file to retrieve.

### Returns
File? - The File at the given index, or null if out of range.
```

--------------------------------

### FileList Interface

Source: https://www.w3.org/TR/FileAPI

The FileList interface represents a list of File objects, typically returned by file input elements or drag-and-drop operations.

```APIDOC
## FileList Interface

### Description
The FileList interface represents a list of File objects. It is array-like and provides access to the files by index.

### Attributes
- `length` (unsigned long) - The number of files in the list.

### Methods
- `item(unsigned long index)` - Returns the File at the given index, or null if the index is out of range.
```

--------------------------------

### Explicitly revoke a blob URL with URL.revokeObjectURL()

Source: https://www.w3.org/TR/FileAPI

Creates a blob URL from a file, assigns it to two Image objects, then revokes it after both images load so subsequent references throw an exception.

```javascript
var blobURLref = URL.createObjectURL(file);
img1 = new Image();
img2 = new Image();

// Both assignments below work as expected
img1.src = blobURLref;
img2.src = blobURLref;

// ... Following body load
// Check if both images have loaded
if(img1.complete && img2.complete) {
  // Ensure that subsequent refs throw an exception
  URL.revokeObjectURL(blobURLref);
}
```

--------------------------------

### File.name

Source: https://www.w3.org/TR/FileAPI

Read-only attribute that returns the name of the file.

```APIDOC
## File.name

### Description
Returns the name of the file.

### Property
readonly attribute DOMString name

### Returns
DOMString - The file name.
```

--------------------------------

### FileReader.readAsText()

Source: https://www.w3.org/TR/FileAPI

Asynchronously reads the Blob as text.

```APIDOC
## FileReader.readAsText()

### Description
Starts reading the specified Blob as text.

### Method
undefined readAsText(Blob blob, optional DOMString encoding)

### Parameters
- **blob** (Blob) - Required - The Blob to read.
- **encoding** (DOMString) - Optional - The encoding to use for the text.

### Returns
undefined
```

--------------------------------

### FileReaderSync.readAsBinaryString()

Source: https://www.w3.org/TR/FileAPI

Synchronously reads the Blob as a binary string.

```APIDOC
## FileReaderSync.readAsBinaryString()

### Description
Synchronously reads the specified Blob as a binary string.

### Method
DOMString readAsBinaryString(Blob blob)

### Parameters
- **blob** (Blob) - Required - The Blob to read.

### Returns
DOMString - The binary string.
```

--------------------------------

### FileList.length

Source: https://www.w3.org/TR/FileAPI

Returns the number of files in the FileList object.

```APIDOC
## FileList.length

### Description
Returns the number of files in the FileList object. If there are no files, returns 0.

### Attribute
- **length** (unsigned long) - readonly - The number of files in the FileList.

### Example
js
var count = fileList.length;

```

--------------------------------

### Blob.text()

Source: https://www.w3.org/TR/FileAPI

Asynchronously reads the Blob's contents as text.

```APIDOC
## Blob.text()

### Description
Returns a Promise that resolves with the contents of the Blob as a USVString (text).

### Method
[NewObject] Promise<USVString> text()

### Returns
Promise<USVString> - A promise that resolves with the text content.
```

--------------------------------

### Blob.size Attribute

Source: https://www.w3.org/TR/FileAPI

Documentation for the Blob.size attribute, which returns the size of the Blob in bytes.

```APIDOC
## [Attribute] Blob.size

### Description
Returns the size of the byte sequence in number of bytes. On getting, conforming user agents must return the total number of bytes that can be read by a FileReader or FileReaderSync object, or 0 if the Blob has no bytes to be read.

### Type
unsigned long long (readonly)

### Response
#### Success Response
- **size** (unsigned long long) - The total number of bytes in the Blob.

```

--------------------------------

### Blob.textStream()

Source: https://www.w3.org/TR/FileAPI

Returns a ReadableStream for reading the Blob's contents as text.

```APIDOC
## Blob.textStream()

### Description
Returns a ReadableStream that can be used to read the contents of the Blob as text.

### Method
[NewObject] ReadableStream textStream()

### Returns
ReadableStream - A stream for reading the Blob's text content.
```

--------------------------------

### Blob Interface

Source: https://www.w3.org/TR/FileAPI

The Blob interface represents immutable raw binary data. It provides constructors, attributes, and methods to access and manipulate the data.

```APIDOC
## Blob Interface

### Description
The Blob interface represents a file-like object of immutable, raw data. It can be constructed from parts and provides methods to read its content in various formats.

### Constructors
- `Blob(optional sequence<BlobPart> blobParts, optional BlobPropertyBag options)` - Creates a new Blob object.

### Attributes
- `size` (unsigned long long) - The size, in bytes, of the Blob.
- `type` (DOMString) - The MIME type of the Blob, lowercased.

### Methods
#### `slice()`
- `Blob slice(optional long long start, optional long long end, optional DOMString contentType)` - Returns a new Blob object containing the bytes in the specified range.

#### `stream()`
- `ReadableStream stream()` - Returns a ReadableStream that can be used to read the contents of the Blob.

#### `text()`
- `Promise<USVString> text()` - Returns a promise that resolves with the contents of the Blob as a string.

#### `arrayBuffer()`
- `Promise<ArrayBuffer> arrayBuffer()` - Returns a promise that resolves with the contents of the Blob as an ArrayBuffer.

#### `bytes()`
- `Promise<Uint8Array> bytes()` - Returns a promise that resolves with the contents of the Blob as a Uint8Array.

#### `textStream()`
- `ReadableStream textStream()` - Returns a ReadableStream that yields the contents of the Blob as text chunks.
```

--------------------------------

### Blob.text()

Source: https://www.w3.org/TR/FileAPI

Returns a Promise that resolves with the contents of the Blob as a USVString (text).

```APIDOC
## [METHOD] Blob.text()

### Description
Returns a Promise that resolves with the contents of the Blob as a USVString (text).

### Method
text

### Endpoint
Blob.text()

### Parameters
None

### Response
#### Success Response
- **Promise<USVString>** - A promise that resolves with the Blob's contents as a string.

#### Response Example
```js
const text = await blob.text();
```
```

--------------------------------

### Blob.text()

Source: https://www.w3.org/TR/FileAPI

The text() method returns a promise that resolves with the contents of the Blob as a string, decoded as UTF-8.

```APIDOC
## [Blob.text()]

### Description
The `text()` method returns a promise that resolves with the contents of the Blob as a string, decoded as UTF-8.

### Method
text

### Endpoint
Blob.text()

### Parameters
None.

### Response
#### Success Response
Returns a Promise that resolves with a DOMString.
```

--------------------------------

### readAsDataURL(blob)

Source: https://www.w3.org/TR/FileAPI

Initiates an asynchronous read of a Blob or File, producing a DataURL.

```APIDOC
## [FileReader] readAsDataURL(blob)

### Description
Initiates a read operation for the given blob, producing a DataURL.

### Method
readAsDataURL

### Parameters
- **blob** (Blob) - Required - The blob to read.

### Response
Returns a DataURL representation of the blob.
```

--------------------------------

### Blob.bytes()

Source: https://www.w3.org/TR/FileAPI

Returns a Promise that resolves with the contents of the Blob as a Uint8Array.

```APIDOC
## [METHOD] Blob.bytes()

### Description
Returns a Promise that resolves with the contents of the Blob as a Uint8Array.

### Method
bytes

### Endpoint
Blob.bytes()

### Parameters
None

### Response
#### Success Response
- **Promise<Uint8Array>** - A promise that resolves with the Blob's contents as a Uint8Array.

#### Response Example
```js
const bytes = await blob.bytes();
```
```

--------------------------------

### FileList.item(index)

Source: https://www.w3.org/TR/FileAPI

Returns the File object at the specified index in the FileList, or null if the index is out of range.

```APIDOC
## FileList.item(index)

### Description
Returns the File object at the specified index in the FileList. If there is no such File object, returns null.

### Method
item(index)

### Parameters
- **index** (unsigned long) - Required - The position of the File object in the FileList, with 0 representing the first file.

### Returns
- **File?** - The File object at the given index, or null if not found.

### Example
js
var file = fileList.item(0);

```

--------------------------------

### FileList.length

Source: https://www.w3.org/TR/FileAPI

Read-only attribute that returns the number of files in the FileList.

```APIDOC
## FileList.length

### Description
Returns the number of files in the FileList.

### Property
readonly attribute unsigned long length

### Returns
unsigned long - The number of files.
```

--------------------------------

### FileReaderSync.readAsText()

Source: https://www.w3.org/TR/FileAPI

Synchronously reads the Blob as text.

```APIDOC
## FileReaderSync.readAsText()

### Description
Synchronously reads the specified Blob as text.

### Method
DOMString readAsText(Blob blob, optional DOMString encoding)

### Parameters
- **blob** (Blob) - Required - The Blob to read.
- **encoding** (DOMString) - Optional - The encoding to use.

### Returns
DOMString - The text content.
```

--------------------------------

### Blob.textStream()

Source: https://www.w3.org/TR/FileAPI

Returns a ReadableStream that can be used to read the contents of the Blob as text.

```APIDOC
## [METHOD] Blob.textStream()

### Description
Returns a ReadableStream that can be used to read the contents of the Blob as text.

### Method
textStream

### Endpoint
Blob.textStream()

### Parameters
None

### Response
#### Success Response
- **ReadableStream** - A ReadableStream for reading the Blob's text content.

#### Response Example
```js
const textStream = blob.textStream();
```
```

--------------------------------

### Blob.bytes()

Source: https://www.w3.org/TR/FileAPI

Asynchronously reads the Blob's contents as a Uint8Array.

```APIDOC
## Blob.bytes()

### Description
Returns a Promise that resolves with the contents of the Blob as a Uint8Array.

### Method
[NewObject] Promise<Uint8Array> bytes()

### Returns
Promise<Uint8Array> - A promise that resolves with the binary data as a Uint8Array.
```

--------------------------------

### FileList interface WebIDL definition

Source: https://www.w3.org/TR/FileAPI

WebIDL definition of the FileList interface, which is a list of File objects. It has a getter for item(index) and a readonly length attribute. The interface is exposed to Window and Worker and is serializable.

```webidl
[Exposed=(Window,Worker), Serializable]
interface FileList {
  getter File? item(unsigned long index);
  readonly attribute unsigned long length;
};
```
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