FileIO class

Provides helper methods for reading and writing files that are represented by objects of type IStorageFile.

Syntax

var fileIO = Windows.Storage.FileIO;

Attributes

MarshalingBehaviorAttribute(Agile)

StaticAttribute(Windows.Storage.IFileIOStatics, NTDDI_WIN8)

ThreadingAttribute(Both)

VersionAttribute(NTDDI_WIN8)

Members

The FileIO class has these types of members:

• Methods

Methods

The FileIO class has these methods. With C#, Visual Basic, and C++, it also inherits methods from the Object class.

Remarks

This class is static and cannot be instantiated. Call the methods directly instead.

To learn more about what locations your app can access, see File access and permissions in Windows Store apps.

To learn how to read and write to files, see Quickstart: Reading and writing a file.

Examples

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

if (file !== null) {
    Windows.Storage.FileIO.writeTextAsync(file, "Swift as a shadow").done(function () {
        // Perform additional tasks after file is written
    },
    // 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 write.

Although the writeTextAsync methods don't have a return value, you can still perform additional tasks after the text is written to the file, as the example shows.

The File Access sample also shows you how to use readTextAsync(file) to read text from a file.

if (file !== null) {
    Windows.Storage.FileIO.readTextAsync(file).done(function (fileContent) {
        // Process content read from the file
    },
    // Handle errors with an error function
    function (error) {
        // Handle errors encountered during read
    });
}

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

After readTextAsync completes, the fileContent variable gets the contents of the file as a text string. You can then process the contents as appropriate.

Requirements

Build date: 2/25/2013