dom-to-image生成图片并下载

1. 下载必要的js库npm install dom-to-image
2. 引用库import domtoimage from ‘dom-to-image’;
   ①生成png的图片插入的到当前页面

var node = document.getElementById('my-node');
domtoimage.toPng(node)
    .then(function (dataUrl) {
        var img = new Image();
        img.src = dataUrl;
        document.body.appendChild(img);
    })
    .catch(function (error) {
        console.error('oops, something went wrong!', error);
    });

②生成图片并下载png格式

domtoimage.toBlob(document.getElementById('my-node'))
  .then(function (blob) {
       window.saveAs(blob, 'my-node.png');
   });

③生成图片并下载jpeg格式

domtoimage.toJpeg(document.getElementById('my-node'), { quality: 0.95 })
    .then(function (dataUrl) {
        var link = document.createElement('a');
        link.download = 'my-image-name.jpeg';
        link.href = dataUrl;
        link.click();
    });
                        

④还两种生成SVG和pixel data的

domtoimage.toSvg(document.getElementById('my-node'), {filter: filter})
    .then(function (dataUrl) {
        /* do something */
    });
 var node = document.getElementById('my-node');
domtoimage.toPixelData(node)
    .then(function (pixels) {
        for (var y = 0; y < node.scrollHeight; ++y) {
          for (var x = 0; x < node.scrollWidth; ++x) {
            pixelAtXYOffset = (4 * y * node.scrollHeight) + (4 * x);
            /* pixelAtXY is a Uint8Array[4] containing RGBA values of the pixel at (x, y) in the range 0..255 */
            pixelAtXY = pixels.slice(pixelAtXYOffset, pixelAtXYOffset + 4);
          }
        }
    });

完整的Demo：

  


  
  
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