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)  },