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up vote 8 down vote favorite
5

At this moment, I am working on a project with Mozilla Europe. In this project, I use websocket by Worlize(server-side) and Mozilla (client side), Node.js to try to upload files from a client to a server.
My present goal is to send a arraybuffer of the file to the server. Create the arraybuffer and send it is fine.
But my server tells me that arraybuffer is a utf8 message and not a binary message.
Do I misunderstand something? If not, how can i correct that?

Sorry,it was not an ad for my github. There is just a lot of code.
In summary:

Client side:

    reader = new FileReader();
    reader.readAsArrayBuffer(file);
    reader.onload = function(e){

            connection.send(e.target.result); 
                        };

Server side:

ws.on('message', function(message,flags){
if(!flags.binary){
   //some code
}
else{
console.log('It\'s a binary');
}

I try with Blob to, same result. The binary part is invisible.

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1  
This is a Q&A site, "fork and participate" isn't going to happen here (see stackoverflow.com/faq). Also, please don't ask people to dig through your code - include the minimal code necessary to explain what exactly you are doing. –  Wladimir Palant Mar 3 '12 at 20:46
    
I realise this was asked some time ago so having said that I just want to add that Firefox 11 and onwards support binary ArrayBuffer and Blob. –  SpliFF Jul 5 '12 at 1:35

2 Answers 2

up vote 9 down vote

Gecko11.0 ArrayBuffer send and receive support for binary data has been implemented.

connection = new WebSocket('ws://localhost:1740');
connection.binaryType = "arraybuffer";
connection.onopen = onopen;
connection.onmessage = onmessage;
connection.onclose = onclose;
connection.onerror = onerror;

sending Binary data:

function sendphoto() {
    imagedata = context.getImageData(0, 0, imagewidth,imageheight);

    var canvaspixelarray = imagedata.data;


    var canvaspixellen = canvaspixelarray.length;
    var bytearray = new Uint8Array(canvaspixellen);

    for (var i=0;i<canvaspixellen;++i) {
        bytearray[i] = canvaspixelarray[i];
    }

    connection.send(bytearray.buffer);
    context.fillStyle = '#ffffff';
    context.fillRect(0, 0, imagewidth,imageheight);    
}

Recieving Binary Data:

if(event.data instanceof ArrayBuffer)
    {

        var bytearray = new Uint8Array(event.data);


        var tempcanvas = document.createElement('canvas');
            tempcanvas.height = imageheight;
            tempcanvas.width = imagewidth;
        var tempcontext = tempcanvas.getContext('2d');

        var imgdata = tempcontext.getImageData(0,0,imagewidth,imageheight);

        var imgdatalen = imgdata.data.length;

        for(var i=8;i<imgdatalen;i++)
        {
            imgdata.data[i] = bytearray[i];
        }

        tempcontext.putImageData(imgdata,0,0);


        var img = document.createElement('img');
            img.height = imageheight;
            img.width = imagewidth;
            img.src = tempcanvas.toDataURL();
        chatdiv.appendChild(img);
        chatdiv.innerHTML = chatdiv.innerHTML + "<br />";
    }
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up vote 0 down vote 
Note: Firefox currently only supports sending strings.

Source: https://developer.mozilla.org/en/WebSockets/Writing_WebSocket_client_applications

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