How can I write a UTF-8-encoded file to the user’s computer using JavaScript on IE?

Question

I am writing a local file using JavaScript and I am using IE for the same.

My code is as follows:

function savefile( f,g){

var w = window.frames.w;
if( !w ) {
    w = document.createElement( 'iframe' );
    w.id = 'w';
    w.style.display = 'none';
    document.body.insertBefore( w );
    w = window.frames.w;
    if( !w ) {
        w = window.open( '', '_temp', 'width=100,height=100' );
        if( !w ) {
            window.alert( 'Sorry, could not create file.' );
            return false;
        }
    }
}

var d = w.document;
d.open( 'text/xml', 'replace');
d.charset = "UTF-8";

d.write(JWPFormToHTML(f));
d.close();
var name= g.filename.value;

if( d.execCommand( 'SaveAs', false , name ) )
{
    g.filename.value=name;
    //document.getElementById("filename").value="";
    alert('File has been saved.' );
}
else
{
    alert( 'The file has not been saved.\nIs there a problem?' );
}
w.close();
return false;
}

The problem I am facing is the file is not getting saved as a UTF-8 encoded file, although I have added <meta http-equiv='Content-Type' content='text/html; charset=utf-8'> to it.

Please help me on this or suggest some alternative to me.

NOTE: I would like a file manager to open before the file gets saved as in the case of execCommand.

Answer 1

Most likely you have an issue with the fact that Windows typically encodes unicode at utf-16 and the browser doesn't care to consider any alternative.

You could go the ActiveX route, The FileSystemObject supports a unicode format flag for text streams but I'd wager it's the same 16 encoding. The ADODB.Stream object however contains a charset property which can be set to a variety of formats including utf-8

http://msdn.microsoft.com/en-us/library/ms526296(v=exchg.10).aspx

Outside of that I think your best bet would be to write a bho or have the specs changed. You will of course need higher permissions manually changed in the browser, but maybe you're lucky and this is an intranet application :D

    var adTypeBinary = 1;
    var adTypeText = 2;
    var adSaveCreateOverwrite = 2;
    var stream = new ActiveXObject("ADODB.Stream");
        stream.Type = adTypeText;
        stream.Charset = "utf-8";
        stream.Open();
        stream.Write(txt);
        stream.SaveToFile(path, adSaveCreateOverwrite);

(*this code was not tested, for example only)