dom/canvas/test/file_drawImage_document_domain.html

   1 <!DOCTYPE html>
   2   <canvas id="c" width="1" height="1"></canvas>
   3   <img id="img" src="image_green-1x1.png">
   4 <script>
   5   window.onmessage = function(ev) {
   6     if (ev.data != "start") {
   7       parent.postMessage({ msg: "unknown_message", data: ev.data }, "*");
   8       return;
   9     }
  10
  11     // Set document.domain to itself, so we trigger the
  12     // "set effective script origin" cases.
  13     // eslint-disable-next-line no-self-assign
  14     document.domain = document.domain
  15     var ctx = document.getElementById("c").getContext("2d");
  16     ctx.drawImage(document.getElementById("img"), 0, 0);
  17     try {
  18       var data = ctx.getImageData(0, 0, 1, 1).data;
  19       parent.postMessage(
  20         {
  21           msg: "color",
  22           data: "rgba(" + data[0] + ", " + data[1] + ", " + data[2] + ", " + data[3]/255 + ")"
  23         },
  24         "*");
  25     } catch (e) {
  26       parent.postMessage({ msg: "exception", data: e.toString() }, "*");
  27     }
  28
  29     parent.postMessage({ msg: "done" }, "*");
  30   }
  31 </script>