无法将html保存为图像（html2canvas）

Question

您好，我正在尝试使用html2canvas将html div保存到图像中。我几乎尝试了所有的东西，但我无法让它发挥作用。

我不熟悉jquery，ajax等。

这是我的javascript和html：

     <script src="/editor/js/jquery.js"></script>
    <script src="/editor/js/html2canvas.js"></script>
    <script type="text/javascript">

    function saveData(dturl){
    dturl.replace(/^data:image\/(png|jpg);base64,/, "");
    $.post( "/editor/canvas/savelogo.php", {img:dturl}, function(data) {
        //$('#recieve').append(data);
    }); 
}

$('.click').click(function(){
    var el = $('#fpd').get(0); 
    html2canvas.Preload(el, {
        complete: function(image){
            var queue = html2canvas.Parse(el, image, {elements: el}),
                $canvas = $(html2canvas.Renderer(queue, {elements: el}));
            saveData($canvas[0].toDataURL());
        }
    });
});
</script>
<button class="click">Save this</button>

PHP代码：

<?php
    # we are a PNG image
    header('Content-type: image/png');

    # we are an attachment (eg download), and we have a name
    header('Content-Disposition: attachment; filename="' . $_POST['name'] .'"');

    #capture, replace any spaces w/ plusses, and decode
    $encoded = $_POST['img'];
    $encoded = str_replace(' ', '+', $encoded);
    $decoded = base64_decode($encoded);

    #write decoded data
    echo $decoded;
?>