function UploadError(sender, args) {
    document.getElementById('lblStatus').innerText = args.get_fileName(),
    "<span style='color:red;'>" + args.get_errorMessage() + "</span>";
}

function StartUpload(sender, args) {
    document.getElementById('lblStatus').innerText = 'Uploading Started.';
}

function UploadComplete(sender, args) {
    var filename = args.get_fileName();
    var contentType = args.get_contentType();
    var text = "Size of " + filename + " is " + args.get_length() + " bytes";
    if (contentType.length > 0) {
        text += " and content type is '" + contentType + "'.";
    }
    document.getElementById('lblStatus').innerText = text;
}