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Save Canvas With Background Image And Text Content As image

How can I save canvas with background data and text content as Image.

I have tried toDataUrl but its returning me only blank canvas.

<canvas id="canvas" width="578" height="250" crossOrigin="Anonymous"></canvas>
<a id="link_save" href="https://google.com/" target="_blank">SAVE</a>

<script>

function wrapText(context, text, x, y, maxWidth, lineHeight) {
    var words = text.split(' ');
    var line = '';

    for(var n = 0; n < words.length; n++) {
      var testLine = line + words[n] + ' ';
      var metrics = context.measureText(testLine);
      var testWidth = metrics.width;
      if (testWidth > maxWidth && n > 0) {
        context.fillText(line, x, y);
        line = words[n] + ' ';
        y += lineHeight;
      }
      else {
        line = testLine;
      }
    }
    context.fillText(line, x, y);
  }

var canvas = document.getElementById('canvas');
var image = new Image();
image.src = './img/bg.jpg';
var base = canvas.toDataURL();
console.log(base);
image.onload = function () {
var context = canvas.getContext('2d');

var width = 500;
var height = 500;
context.drawImage(image, 10, 0, 300, 200); // resizes image to 300px wide, 200px high


  var maxWidth = 400;
  var lineHeight = 25;
  var x = (canvas.width - maxWidth) / 2;
  var y = 60;
  var text = 'All the world \'s a stage, and all the men and women merely players. They have their exits and their entrances; And one man in his time plays many parts.';

  context.font = '16pt Calibri';
  context.fillStyle = '#333';

  wrapText(context, text, x, y, maxWidth, lineHeight);
};

</script>

I have tried saving canvas but only returns blank canvas, not with content.

You call canvas.toDataUrl() before the image has been load.

Put the code at the end of onload event

image.onload = function () {

    // Do stuff...

    var base = canvas.toDataURL();
    console.log(base);
}

Another hack: After your done manipulate...just right click in your browser on the canvas and save as .png ;)

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