How to write UTF-8 or Base64 data into a file (jpg/doc/pdf) on local storage(sdcard) in Phonegap

Question

I am getting byte array like var byteArr=[12,-123,43,99, ...] from API, Then I am converting it into UTF-8 String by

     var utf8_str = String.fromCharCode.appl         


        

Answer 1

try this (make sure u are getting utf8_str properly):

var utf8_str = String.fromCharCode.apply([], new Uint8Array(byteArr));
var base64_str= window.btoa(utf8_str);
function writeFile() {
    window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, gotFS, fail);
}
function gotFS(fileSystem) {
    fileSystem.root.getFile(FILE_NAME, {create: true}, gotFileEntry, fail);
}
function gotFileEntry(fileEntry) {
    fileEntry.createWriter(gotFileWriter, fail);
}
function gotFileWriter(writer) {
    writer.onwrite = function (evt) {
        alert('done');
    }
    writer.write(utf8_str);
}
function fail(error) {
    console.log(error.code);
}