渲染具有对Canvas的外部引用的SVG [英] Render SVG with external references to Canvas

问题描述

我想使用 data：URI 和 canvas.drawImage（）。

示例HTML（ live jsFiddle example ）：

<canvas id="canvas" width="400" height="400"></canvas>
<div id="container">
    <svg id="mySVG" xmlns="http://www.w3.org/2000/svg" version="1.1">
      <rect width="150" height="150" fill="rgb(0, 255, 0)" stroke-width="1" stroke="rgb(0, 0, 0)"/>
      <image preserveAspectRatio="none" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://upload.wikimedia.org/wikipedia/en/7/70/Example.png" width="80" height="80"></image>
    </svg>
</div>

Javascript：

Javascript:

var canvas = document.getElementById('canvas'),
    ctx = canvas.getContext('2d'),
    svg = document.getElementById('container').innerHTML,
    img = new Image();

img.onload = function () {
    ctx.drawImage(img, 0, 0);
};
img.src = 'data:image/svg+xml,' + svg;

我尝试在调用drawImage之前设置一个超时，希望这将是一个同步问题，但是它似乎没有帮助。任何想法？

I've tried setting a timeout before calling drawImage, hoping that it would be a synchronization issue, but it did not seem to help. Any ideas?

推荐答案

这不是画布问题。它不会工作/将看起来相同，即使你不使用画布，只是将您的HTMLImageElement附加到DOM。请参阅：

This is not a canvas issue. It won't work/will look the same even if you are not using the canvas at all and just appending your HTMLImageElement to the DOM. see:

    var svg = document.getElementById('container').innerHTML,
    img = new Image();

img.onload = function () {
    document.body.appendChild(img); // img does not contain Wikipedia image
};
img.src = 'data:image/svg+xml,' + svg;

http://jsfiddle.net/ss5bjooj/2/

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