Question

我想为我的浏览器制作最简单的书记。

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.

My console tells me: Uncaught TypeError: Cannot set property display of undefined

当我点击这本书记册时,应该看看一看。我在这里做了什么错误?

Answer 1

或许需要取得结果,例如:

var divs = document.getElementsByClassName( source );
for(var i=0; i<divs.length; i++) { 
  divs[i].style.display= block 
}

并且正如“@ionoy”提到的那样,使用<代码><>>>>>>属性。我希望能够提供帮助。

rel=“noretinger”>http://jsfiddle.net/erick/rb7bn/1/

Answer 2

可见一斑。它们是不同的。

W3Schools:

Answer 3

www.un.org/Depts/DGACM/index_french.htm 它与许多浏览器和很多情况下的浏览器合作。

Answer 4

Here is the efficeint solution:

let divs = [...document.getElementsByClassName( source )];
divs.forEach(divEl => {
  divEl.style.display= block 
}

using [...HTMLcollection] perfix converts the HTMLcollection to an array, then you can itarate it.