多端生成图片

备忘

多端生成图片：

createImg(store, data) {
    let timer = setTimeout(function (params) {
      let _canvas = document.querySelector(".setPictureSection");
      var w = parseInt(window.getComputedStyle(_canvas).width);
      var h = parseInt(window.getComputedStyle(_canvas).height);
      var scale = 6;
      var canvas = document.createElement("canvas");
      canvas.width = w * 2;
      canvas.height = h * 2;
      canvas.style.width = w + "px";
      canvas.style.height = h + "px";
      var context = canvas.getContext("2d");
      context.scale(2, 2);

      var opts = {
        // allowTaint:true,
        useCORS: true,
        logging: false,
        scale: scale,
        dpi: window.devicePixelRatio * scale,
        canvas: canvas,
        width: w,
        heigth: h
      };
      console.log(opts)

      function dImg(canvas) {
        document.querySelector(".down").setAttribute("href", canvas.toDataURL("image/png", 1.0));
        $(".down")[0].click();
      }
      html2canvas.html2canvas(_canvas, opts).then(function (canvas) {
        dImg(canvas)
      });
      
      clearInterval(timer)
    }, 350)
  },