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File

The File interface provides information about files and allows JavaScript in a web page to access their content.

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Extends

Methods

arrayBuffer()

arrayBuffer(): Promise<ArrayBuffer>;

The arrayBuffer() method of the Blob interface returns a Promise that resolves with the contents of the blob as binary data contained in an ArrayBuffer.

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Returns

Promise<ArrayBuffer>

Inherited from

Blob.arrayBuffer


bytes()

bytes(): Promise<Uint8Array<ArrayBuffer>>;

The bytes() method of the Blob interface returns a Promise that resolves with a Uint8Array containing the contents of the blob as an array of bytes.

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Returns

Promise<Uint8Array<ArrayBuffer>>

Inherited from

Blob.bytes


slice()

slice(
start?,
end?,
contentType?
): Blob;

The slice() method of the Blob interface creates and returns a new Blob object which contains data from a subset of the blob on which it's called.

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Parameters

ParameterType
start?number
end?number
contentType?string

Returns

Blob

Inherited from

Blob.slice


stream()

stream(): ReadableStream<Uint8Array<ArrayBuffer>>;

The stream() method of the Blob interface returns a ReadableStream which upon reading returns the data contained within the Blob.

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Returns

ReadableStream<Uint8Array<ArrayBuffer>>

Inherited from

Blob.stream


text()

text(): Promise<string>;

The text() method of the Blob interface returns a Promise that resolves with a string containing the contents of the blob, interpreted as UTF-8.

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Returns

Promise<string>

Inherited from

Blob.text

Properties

lastModified

readonly lastModified: number;

The lastModified read-only property of the File interface provides the last modified date of the file as the number of milliseconds since the Unix epoch (January 1, 1970 at midnight). Files without a known last modified date return the current date.

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name

readonly name: string;

The name read-only property of the File interface returns the name of the file represented by a File object. For security reasons, the path is excluded from this property.

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size

readonly size: number;

The size read-only property of the Blob interface returns the size of the Blob or File in bytes.

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Inherited from

Blob.size


type

readonly type: string;

The type read-only property of the Blob interface returns the MIME type of the file.

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Inherited from

Blob.type


webkitRelativePath

readonly webkitRelativePath: string;

The webkitRelativePath read-only property of the File interface contains a string which specifies the file's path relative to the directory selected by the user in an <input> element with its webkitdirectory attribute set.

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