Download zip file (contains xml and images) through ajax and store binary data in localstorage in IE - ajax

Question

I was able to download the zip file (2mb) from server through ajax call and storing binary data in the web storage where as this is not working in IE (7,8,9). Below is my code.
var req = new XMLHttpRequest();
req.open('GET', filename, false);
req.onreadystatechange=function()
{
if (req.readyState == 4)
{
if(req.status!=200){
chk_file = false;
alert('Sorry, Error occured while downloading the question paper. HTTP Error Code: '+req.status);
}
}
}
if (req.overrideMimeType) {
req.overrideMimeType('text/plain; charset=x-user-defined');
} else {
req.setRequestHeader('Accept-Charset', 'x-user-defined');
}
req.send('hello');
var buffer = "";
var dbata;
try {
bdata = BinaryToArray(req.responseBody).toArray();
for (var i = 0, len = bdata.length - 1; i < len; i++) {// dbata is one byte too long. Why ???
buffer += String.fromCharCode(bdata[i] & 0xFF);
}
} catch(e) {
bdata = req.responseText;
for (var i = 0, len = bdata.length; i < len; i++) {
buffer += String.fromCharCode(bdata.charCodeAt(i) & 0xFF);
}
}
Converting Binary data to array in VB script . following is the code.
var IE_HACK = (/msie/i.test(navigator.userAgent) &&
!/opera/i.test(navigator.userAgent));
if (IE_HACK) {
var vbScript = '<scr' + 'ipt type="text/vbscript">\n'+
'<!-' + '-\n' +
'Function BinaryToArray(Binary)\n'+
' Dim i\n'+
' ReDim byteArray(LenB(Binary))\n'+
' For i = 1 To LenB(Binary)\n'+
' byteArray(i-1) = AscB(MidB(Binary, i, 1))\n'+
' Next\n'+
' BinaryToArray = byteArray\n'+
'End Function\n'+
'--' + '>\n' +
'</scr' + 'ipt>';
//$(vbScript).insertAfter("script:last");
document.write(vbScript);
Storing this buffer value in html5 web storage.
I am not getting complete content in IE where it is working in FF, Chrome.
Any help!

Answer 1

Maybe this can help you, but guess you solved this by now, but it might help people that sees this question
is there a cross-browser alternative to the xhr.overrideMimeType() function?
https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/Sending_and_Receiving_Binary_Data
https://github.com/eligrey/FileSaver.js
http://stuk.github.io/jszip/