var openFile = function(event) {
        var input = event.target;
        var reader = new FileReader();
        reader.onload = function(){
            var arrayBuffer = reader.result;
            var bl= new Blob([arrayBuffer],{type: "text/json;charset=utf-8"});
            webSocket.send(bl);
        };
        reader.readAsArrayBuffer(input.files[0]);
    };