我已经寻找了答案，但似乎没有解决方案可以解决这个问题，所以希望具体说明它能帮助我找到解决方案。
我尝试使用 document.styleSheets[0].cssText 读取第一个样式表的 cssText，但它总是返回 undefined。我确实有一个样式表，而且它非常明显，但 JavaScript 似乎无法识别它。
然而，当我使用
感谢您的任何帮助。
编辑：这适用于 any 与 document.styleSheets[0] 的方法，包括那些应该在多个浏览器上工作并且在使用 <链接>。例如：document.styleSheets[0].cssRules[0].selectorText
I've searched for an answer and no solution seems to fix this problem, so hopefully stating it specifically will help me find a solution.
I'm trying to read cssText of the first stylesheet using document.styleSheets[0].cssText, but it always returns undefined. I do have a stylesheet and it's visibly noticeable, but JavaScript doesn't seem to recognize it.
This did, however, work when I included the stylesheet within the page using <style>. I don't see why this would change when using <link>, though. Not only is it placed before the script, but it even returns undefined when using javascript:alert(document.styleSheets[0].cssText) in the omnibar after the page is fully loaded.
Thanks for any help.
Edit: This applies to any method with document.styleSheets[0], including those of which are supposed to work on multiple browsers and have worked for me prior to using <link>. For example: document.styleSheets[0].cssRules[0].selectorText
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根据 quirksmode.org，
document.styleSheets[n].cssText 仅在 IE 中受支持。该表单
似乎得到了更广泛的支持，因此您可以循环遍历该表单并根据各个规则构建一个字符串。 （尽管对于 IE，您必须将
cssRules替换为rules）。According to quirksmode.org,
document.styleSheets[n].cssTextis only supported in IE.The form
seems to be more widely supported, so you could just loop over that and build a string from the individual rules. (Although you have to replace
cssRuleswithrulesfor IE).我认为这个答案已经过时了，但对其他人可能有用。
由于 2 个不同的原因，结果可能是“未定义”：
a) 在某些浏览器中，属性“cssRules”不起作用（根据 http://www.javascriptkit.com/domref/cssrule.shtml，仅在 NS/ Firefox 中受支持）。对于其他浏览器，您应该使用属性“rules”。
您可以使用以下方法解决问题：
提取规则，然后提取选择器的名称：
b) 超越问题 a) 后，您可能会遇到另一个问题： 以 @ 开头的规则，例如@import of @font-face，视为规则。然而，他们的“selectorText”是未定义的。所以，你必须有办法跳过它们。我现在正在努力。但我还没有找到解决办法。无论如何，了解它的发生方式是有帮助的。
希望这有帮助
I thing that this answer is out of time, but it could be useful for someone else.
The result can be "undefined" due 2 different reasons:
a) In some browsers, the property "cssRules" does not work (in accord with http://www.javascriptkit.com/domref/cssrule.shtml, only for supported in NS/ Firefox). For the other browser, you should use the property "rules", instead.
You can solve the problem using something like:
to extract the rule and, afterwards, to extract the name of selector:
b) After the overpassing of the issue a), you may have another problem: The rules that starts with a @, like @import of @font-face, as considered as rules. However, their "selectorText" is undefined. So, you must have a way of skip them. I am working on it, right now. But I have not found yet a solution. Anyway, it is an help to know way it is happening.
Hope this helps