FileReader is an object that allows one to read a file.
The FileReader
object is a way to read files from the devices file system. Files can be read as text or as a base64 data encoded string. Users register their own event listners to receive the loadstart, progress, load, loadend, error and abort events.
Parameters:
function win(file) { var reader = new FileReader(); reader.onloadend = function(evt) { console.log("read success"); console.log(evt.target.result); }; reader.readAsDataURL(file); }; var fail = function(evt) { console.log(error.code); }; entry.file(win, fail);
Parameters:
function win(file) { var reader = new FileReader(); reader.onloadend = function(evt) { console.log("read success"); console.log(evt.target.result); }; reader.readAsText(file); }; var fail = function(evt) { console.log(error.code); }; entry.file(win, fail);
function win(file) { var reader = new FileReader(); reader.onloadend = function(evt) { console.log("read success"); console.log(evt.target.result); }; reader.readAsText(file); reader.abort(); }; function fail(error) { console.log(error.code); } entry.file(win, fail);
<!DOCTYPE html> <html> <head> <title>FileReader Example</title> <script type="text/javascript" charset="utf-8" src="phonegap.js"></script> <script type="text/javascript" charset="utf-8"> // Wait for PhoneGap to load // function onLoad() { document.addEventListener("deviceready", onDeviceReady, false); } // PhoneGap is ready // function onDeviceReady() { window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, gotFS, fail); } function gotFS(fileSystem) { fileSystem.root.getFile("readme.txt", null, gotFileEntry, fail); } function gotFileEntry(fileEntry) { fileEntry.file(gotFile, fail); } function gotFile(file){ readDataUrl(file); readAsText(file); } function readDataUrl(file) { var reader = new FileReader(); reader.onloadend = function(evt) { console.log("Read as data URL"); console.log(evt.target.result); }; reader.readAsDataURL(file); } function readAsText(file) { var reader = new FileReader(); reader.onloadend = function(evt) { console.log("Read as text"); console.log(evt.target.result); }; reader.readAsText(file); } function fail(evt) { console.log(evt.target.error.code); } </script> </head> <body> <h1>Example</h1> <p>Read File</p> </body> </html>