examples/phonegap1/plugins/cordova-plugin-file/www/FileReader.js
function() {
    this._readyState = 0;
    this._error = null;
    this._result = null;
    this._progress = null;
    this._localURL = '';
    this._realReader = origFileReader ? new origFileReader() : {};
}
function() {
    this._readyState = 0;
    this._error = null;
    this._result = null;
    this._progress = null;
    this._localURL = '';
    this._realReader = origFileReader ? new origFileReader() : {};
}
function ( ) { this . _readyState = 0 ; this . _error = null ; this . _result = null ; this . _progress = null ; this . _localURL = '' ; this . _realReader = origFileReader ? new origFileReader ( ) : { } ; }
This class reads the mobile device file system.

For Android:
The root directory is the root of the file system.
To read from the SD card, the file name is "sdcard/my_file.txt"
@constructor
This class reads the mobile device file system .