javascript - Capture a div and save as jpeg - Stack Overflow

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#cap is a div i want to capture. I used ctx.drawImage($('#cap').get(0),0,0,640,480);window.open(canvas.getDataURL('image/jpeg'));

got a Type error and how do i send it to php to save as a.jpeg

UPDATE

/ is not working help html2canvas is not a function

#cap is a div i want to capture. I used ctx.drawImage($('#cap').get(0),0,0,640,480);window.open(canvas.getDataURL('image/jpeg'));

got a Type error and how do i send it to php to save as a.jpeg

UPDATE

http://jsfiddle/3qNJB/ is not working help html2canvas is not a function

• javascript
• php
• jquery
• canvas

Share Improve this question Follow edited Jun 12, 2014 at 10:59 user3508453 asked Jun 11, 2014 at 18:11 user3508453user3508453 88833 gold badges1414 silver badges2424 bronze badges

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2 Answers 2

Sorted by: Reset to default 5

< DIV > elements cannot be drawn on canvas using drawImage() method.Have a look at Html2Canvas library

Example:

 html2canvas(document.getElementById('DivToCapture'), {
      onrendered: function(canvas) {
         // document.body.appendChild(canvas);
       window.open(canvas.toDataURL('image/jpeg'));
     }
  });

Heres the Fiddle

Instead of opening the image with javascript, just POST it to your server so PHP can receive it, save it on the server, and then send it back to the browser.

I found this DivsToJPG() function here: Convert html div having multiple images to single image using javascript

var DivsToJPG = function( parent ) {
    this.canvasSizeX = 0;
    this.canvasSizeY = 0;
    this.init = function( parent ) {
        this.images = parent.find('img');
        this.setSizes();
        this.createCanvas();
        this.drawImages();
        this.exportJPG();
    }

    this.setSizes = function() {
        for (var i = 0, l = this.images.length; i < l ; i++) {
            var currentImage = this.images.eq(i);
            var posX = currentImage.position().left;
            var width = currentImage.width();
            this.canvasSizeX = this.canvasSizeX > (posX+width) ? this.canvasSizeX : posX + width;
            //console.log(this.canvasSizeX);
            var posY = currentImage.position().top;
            var height = currentImage.height();
            this.canvasSizeY = this.canvasSizeY > (posY+height) ? this.canvasSizeY : posY + height;

         }
    }

    this.createCanvas = function() {
        this.canvas = document.createElement('canvas');
        this.canvas.id     = "exportCanvas";
        this.canvas.width  = this.canvasSizeX;
        this.canvas.height = this.canvasSizeY;
        this.ctx = this.canvas.getContext("2d");
        document.body.appendChild(this.canvas);
    }

    this.drawImages = function() {
        for (var i = 0, l = this.images.length; i < l ; i++) {
            var currentImage = this.images[i];
            var $currentImage = this.images.eq(i);
            this.ctx.drawImage(currentImage, $currentImage.position().left, $currentImage.position().top, $currentImage.width(), $currentImage.height());
        }
    }

    this.exportJPG = function() {
        var dataURL = this.canvas.toDataURL();
        this.img = document.createElement('img');
        this.img.id = "createdImage";
        this.img.src     = dataURL;
        document.body.appendChild(this.img);
    }

    this.init( parent );
}

var divsToJPG = new DivsToJPG($('#cap'));

$.ajax({
  type : "POST",
  url  : "make-image.php",
  data : { 
     imgBase64 : divsToJPG
  }
}).done(function(data) {

});

Then in PHP

$img = base64_decode($_POST['imgBase64']);

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