javascript getElementsByClassName() 总是不返回？
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javascript getElementsByClassName() always returns none?
提问by matt
hey guys, i wanna create the simplest bookmarklet for my browser.
嘿伙计们，我想为我的浏览器创建最简单的书签。
javascript:document.getElementsByClassName('source').style.visibility='visible';
I have multiple div.source in my body. By default they are set to .source { display:none; }with css.
我的身体中有多个 div.source 。默认情况下，它们设置为.source { display:none; }使用 css。
My console tells me: Uncaught TypeError: Cannot set property 'display' of undefined
我的控制台告诉我： Uncaught TypeError: Cannot set property 'display' of undefined
When I click the bookmarklet all .source divs should be visible. What am I doing wrong here?
当我单击书签时，所有 .source div 都应该可见。我在这里做错了什么？
回答by erickb
You might need to loop through the results, like this:
您可能需要遍历结果，如下所示：
var divs = document.getElementsByClassName('source');
for(var i=0; i<divs.length; i++) {
divs[i].style.display='block'
}
And also as @ionoy mentioned, use displayattribute. I hope that helps.
而且正如@ionoy 提到的，使用display属性。我希望这有帮助。
回答by ionoy
There is 'visibility' and there is 'display'. They are quite different beasts.
有“可见性”和“显示”。他们是完全不同的野兽。
W3Schools:
W3学校：
回答by Dinesh
Go for display. It's works fine with many browsers and in many cases.
去吧display。它在许多浏览器和许多情况下都可以正常工作。
