html2canvas output selected div PHP - php

Question

this code almost works
this will output the entire page into a jpg
question: how can i grab only the content inside '#myDiv' and output that as a jpg file?
JS:
$('.myButton').click(function(){
$('#myDiv').html2canvas();//<< has no effect
var queue = html2canvas.Parse();
var canvas = html2canvas.Renderer(queue,{elements:{length:0}});
var img = canvas.toDataURL();
img.replace(/^data:image\/(png|jpg);base64,/, "");
$.post( "postIO.php", {img:img}, function(data) {
//$('#recieve').append(data);
});
return false;
});
postIO.php:
$canvasImg = $_POST['img'];
//$canvasImg = str_replace('data:image/png;base64,', '', $canvasImg);
$data = base64_decode($canvasImg);
$File = "z.jpg";
$Handle = fopen($File, 'w');
fwrite($Handle, $data);
fclose($Handle);
reference from here

Answer 1

I have download and try html2canvas, then I find out the jquery plugin does not complete (it's does nothing than capture the image and create canvas, no use) so I write capture code myself.
var el = $('div').get(0);
function saveData(dturl){
//Upload here
console.debug(dturl);
}
html2canvas.Preload(el, {
complete: function(image){
var queue = html2canvas.Parse(el, image, {elements: el}),
$canvas = $(html2canvas.Renderer(queue, {elements: el}));
saveData($canvas[0].toDataURL());
}
});
Hope it help you
so to use with your program you have to write
function saveData(dturl){
dturl.replace(/^data:image\/(png|jpg);base64,/, "");
$.post( "postIO.php", {img:dturl}, function(data) {
//$('#recieve').append(data);
});
}
$('.myButton').click(function(){
var el = $('#myDiv').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());
}
});
});

Answer 2

after var canvasImg = canvasRecord.toDataURL("image/jpg");, you may need to replace it using var data = canvasImg.replace(/^data:image\/(png|jpg);base64,/, "");
and is that $canvasImg = $_POST['canvasImg']; instead of $_POST['img']?