FileIO.ReadBufferAsync | readBufferAsync method

Applies to Windows and Windows Phone

Reads the contents of the specified file and returns a buffer.

Syntax


Windows.Storage.FileIO.readBufferAsync(file).done( /* Your success and error handlers */ );

Parameters

file

Type: IStorageFile

The file to read.

Return value

Type: IAsyncOperation<IBuffer>

When this method completes, it returns an object (type IBuffer) that represents the contents of the file.

Examples

The File Access sample shows you how to use writeTextAsync(file, contents) to write text to a file, like this:



if (file !== null) {
    Windows.Storage.FileIO.readBufferAsync(sampleFile).then(function (buffer) {
        // Perform additional tasks after file is read

        // Use a dataReader object to read from the buffer
        var dataReader = Windows.Storage.Streams.DataReader.fromBuffer(buffer);
        var fileContent = dataReader.readString(buffer.length);
        dataReader.close();
    },
    // Handle errors with an error function
    function (error) {
        // Handle errors encountered during write
    });
}

In the example, file is a local variable that contains a storageFile that represents the file to read.

After readTextAsync completes, the buffer variable gets the contents of the file as an IBuffer object. You can then read from the buffer using a dataReader object and process the file contents as appropriate (as shown in the example.)

Requirements

Minimum supported client

Windows 8

Minimum supported server

Windows Server 2012

Minimum supported phone

Windows Phone 8.1 [Windows Phone Silverlight 8.1 and Windows Runtime apps]

Namespace

Windows.Storage
Windows::Storage [C++]

Metadata

Windows.winmd

See also

FileIO

 

 

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