我想在 svg 中替换另一个渐变，所以我需要迭代（可能递归）每个 svg 项目以获得
我查看了 svg doc @ MDN https://developer.mozilla.org/fr/SVG/Element/ellipse 但它已损坏（访问被拒绝，没有示例，很多损坏的链接）
和 MSDN 上的完全不同 http://msdn.microsoft.com/en-us/library/ie/ff972071%28v=vs.85%29.aspx
所以我搜索有关如何访问 svg 元素的填充属性的任何指针，但是它已被定义。类似于 getComputedFill 函数
<svg
version="1.1"
xmlns="http://www.w3.org/2000/svg"
xmlns:svg="http://www.w3.org/2000/svg"
xmlns:dc="http://purl.org/dc/elements/1.1/"
xmlns:cc="http://creativecommons.org/ns#"
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
>
<defs>
<script>
<![CDATA[
function infothis(ref)
{
alert(ref + " " + ref.fill + " " + ref.fillOpacity); // why can't I get "url(#grad1)" and 0.5 when clicking ellipse1
//alert(ref.style.getPropertyValue("fill")); // somewhat okwhy can't I get "url(#grad2)" when clicking ellipse2
}
]]>
</script>
<linearGradient
dc:title="red black filter"
dc:rights="CC-BY"
dc:description="basic filter ranging from black to red"
id="grad1" x1="0%" y1="0%" x2="100%" y2="0%">
<stop offset="0%" style="stop-color:rgb(0,0,0);stop-opacity:1" />
<stop offset="100%" style="stop-color:rgb(255,0,0);stop-opacity:1" />
</linearGradient>
<linearGradient id="grad2" x1="0%" y1="0%" x2="100%" y2="0%">
<stop offset="0%" style="stop-color:rgb(0,0,0);stop-opacity:1" />
<stop offset="100%" style="stop-color:rgb(255,0,255);stop-opacity:1" />
</linearGradient>
<ellipse id="ellipse0" cx="150" cy="170" rx="85" ry="55" fill="url(#grad2)" />
</defs>
<ellipse id="ellipse1" cx="200" cy="70" rx="85" ry="55" fill="url(#grad1)" fill-opacity="0.5" onclick="infothis(this)" />
<ellipse id="ellipse2" cx="100" cy="70" rx="85" ry="55" style="fill:url(#grad2)" onclick="infothis(this)" />
<use xlink:href="#ellipse0"/>
</svg>