Saving canvas as a PNG or JPG

Question

I want to save canvas as PNG, without opening it in a new window as base64-encoded image.

I used this code:

jQuery("#btnPreview").click(function(){
        if (!fabric.Canvas.supports('toDataURL')) {
            alert('Sorry, your browser is not supported.');
        }
        else {
            canvas.deactivateAll();
            canvas.forEachObject(function(o){
                if(o.get("title") == "||Watermark||"){
                    canvas.bringToFront(o);
                }
            });
            window.open(canvas.toDataURL('png'), "");
            canvas.forEachObject(function(o){
                if(o.get("title") == "||Watermark||"){
                    canvas.sendToBack(o);
                }
            });
            canvas.renderAll();
        }

    });

I want to make the button save the image as a PNG or JPG.

Answer 1

canvas.toDataURL('png') provides a string a la data:image/png;base64,XYZ. You could stuff that into an <a href="%dataURI%" download>download</a> (possibly trigger a click event on the element). See Downloading resources in HTML5: a[download]

Currently supported only by Google Chrome, though.

Answer 2

In script.js file

  $(document).on('click','#btnPreview',function(){
     var img =$scope.canvas.toDataURL('image/png');
     $.ajax({
                type: "POST",   
                url: 'ajax.php', 
                data: {'img':img},
                success: function(data) { 
                    $("#loader_message").html("Image saved successfully"); 
                }
            });
  });

In ajax.php

    $encodedData=explode(',', $_POST["img"]);
    $data = base64_decode($encodedData[1]);
    $urlUploadImages = $_SERVER['DOCUMENT_ROOT'].$projName.'/images/canvas/';
    $nameImage = "test.png";
    $img = imagecreatefromstring($data);
     if($img) {
        imagepng($img, $urlUploadImages.$nameImage, 0);
        imagedestroy($img); 
        echo "OK";
    }
    else {
        echo 'ERROR';
    }

Answer 3

I use this on my jquery:

var image = canvas.toDataURL("image/png").replace("image/png", "image/octet-stream"); 

$('.save').attr({
    'download': 'YourProduct.png',  /// set filename
    'href'    : image              /// set data-uri
});