Print page using html2canvas

Question

I'm building a print page function on my web using html2canvas.

function printthispage() {

    html2canvas($("#mydiv"), {
        onrendered: function (canvas) {
            var myImage = canvas.toDataURL("image/png");
            var printWindow = window.open(myImage);                        
            printWindow.document.close();
            printWindow.focus();
            printWindow.print();
            printWindow.close();
        }
    });
}

However the window opened and closed immediately. I've tried removing close(), the image showed on new window but no print function was triggered. Is there something wrong?

Answer 1

Finally I figure out the solution. The previous handling I used should be made into 2 parts.

1) use html2canvas to render the page into image and store it in a hidden div, when the page is loaded.

html2canvas(divprint, {
    onrendered: function(canvas) {
        var canvasImg = canvas.toDataURL("image/jpg");
        $('#divhidden').html('<img src="'+canvasImg+'" alt="">');
    }
});

2) Once a print button is clicked, open a new window, write the stored div content and jquery function for printing when the loading is done.

$("#printbutton").click(function(e){
    var printContent = document.getElementById("divhidden");
    var printWindow = window.open("", "","left=50,top=50");                
    printWindow.document.write(printContent.innerHTML);
    printWindow.document.write("<script src=\'http://code.jquery.com/jquery-1.10.1.min.js\'><\/script>");
    printWindow.document.write("<script>$(window).load(function(){ print(); close(); });<\/script>");
    printWindow.document.close();                
})