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    FileEntry

    Non-standard
    This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

    The FileEntry interface of the File System API represents a file in a file system. It lets you write content to a file.

    About this document

    This document was last updated on March 2, 2012 and follows the W3C Specifications (Working Draft) drafted on April 19, 2011.

    This specification is more or less abandoned as it didn't get significant traction among browser makers.

    Basic concepts

    To write content to file, create a FileWriter object by calling createWriter().

    Example

    The following code creates an empty file called "log.txt" (if it doesn't exist) and fills it with the text 'Meow'. Inside the success callback, event handlers are set up for error and writeend events. The text data is written to the file by creating a blob, appending text to it, and passing the blob to FileWriter.write().

    function onInitFs(fs) {
    
      fs.root.getFile('log.txt', {create: true}, function(fileEntry) {
    
        // Create a FileWriter object for our FileEntry (log.txt).
        fileEntry.createWriter(function(fileWriter) {
    
          fileWriter.onwriteend = function(e) {
            console.log('Write completed.');
          };
    
          fileWriter.onerror = function(e) {
            console.log('Write failed: ' + e.toString());
          };
    
          // Create a new Blob and write it to log.txt.
          var bb = new BlobBuilder(); 
         // Note: window.WebKitBlobBuilder.
          bb.append('Meow');
          
          fileWriter.write(bb.getBlob('text/plain'));
    
        }, errorHandler);
    
      }, errorHandler);
    
    }
    
    window.requestFileSystem(window.TEMPORARY, 1024*1024, onInitFs, errorHandler);

    Method overview

    void createWriter (FileWriterCallback successCallback, optional ErrorCallback errorCallback);
    void file (FileCallback successCallback, optional ErrorCallback errorCallback);

    Methods

    createWriter()

    Creates a new FileWriter object associated with the selected file.

    void createWriter (
     in FileWriterCallback successCallback, optional ErrorCallback errorCallback
    );
    Parameters
    successCallback
    A callback that is called with the new FileWriter object.
    errorCallback
    A callback that is called when errors happen.
    Returns
    void

    file()

    Returns a File object associated with the selected file. You can use this to read the file's content.

    void file (
      FileCallback successCallback, optional ErrorCallback errorCallback
    );
    Parameters
    successCallback
    A callback that is called with the new File.
    errorCallback
    A callback that is called when errors happen.
    Returns
    void

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
    Basic support 13webkit Not supported Not supported Not supported Not supported
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
    Basic support Not supported 0.16webkit Not supported Not supported Not supported Not supported

    See also

    Specification: File API: Directories and System SpecificationWD

    Reference: File System API

    Introduction: Basic Concepts About the File System API

    Document Tags and Contributors

    Contributors to this page: Sheppy, fscholz, teoli, Cobra, grendel, imran1008
    Last updated by: fscholz,