Javascript element.setAttribute 不是函数
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element.setAttribute is not a function
提问by Lazarus Rising
So, i know that this has already been answered, but none of the previous answers managed to make my code work. I have a html structure as the following:
所以，我知道这已经得到了回答，但是以前的答案都没有使我的代码工作。我有一个 html 结构如下：
<div class="form">
<div class="formrow">
<div class="previewcontainer">
<object id="preview">
<object>
</div>
</div>
</div>
I am trying to set the data attribute to the object like this:
我正在尝试将数据属性设置为这样的对象：
var link = "http://www.someurl.com";
var preview = document.querySelectorAll ("#preview");
preview.setAttribute("data", link);
However, I get an error preview.setAttribute is not a function
但是，我收到一个错误 preview.setAttribute is not a function
回答by Maanus Indov
or this:
或这个：
var link = "http://www.someurl.com";
var preview = document.getElementById("preview"); //getElementById instead of querySelectorAll
preview.setAttribute("data", link);
Be sure to run the code after the element is created, or use jQuery code:
确保在创建元素后运行代码，或者使用 jQuery 代码：
$( document ).ready(function() {
}
"Uncaught TypeError: Cannot read property 'setAttribute' of null"
“未捕获的类型错误：无法读取 null 的属性‘setAttribute’”
By: LazarusRising—in that case, the element doesn't exist yet in the document. You need to run the code after the element is created, say after the load event or a script below the element.
作者：LazarusRising——在这种情况下，文档中还不存在该元素。您需要在创建元素后运行代码，例如在加载事件或元素下方的脚本之后。
回答by Victor Akanam
when using querySelectorAll(), treat this as an array, you need a 'for loop' to step through the different elements. eg.
使用 querySelectorAll() 时，将其视为数组，您需要一个“for 循环”来遍历不同的元素。例如。
var link = "http://www.someurl.com";
var preview = document.querySelectorAll ("#preview");
for (var i = 0; i < preview.length; i++ {
preview[i].setAttribute("type", 'href');
}
This will now change the 'type attributes' of all the elements with an id of 'preview' to a link.
现在，这会将所有具有“预览”ID 的元素的“类型属性”更改为链接。
回答by Alexandr Kudryashov
try this:
尝试这个：
var link = "http://www.someurl.com";
var preview = document.querySelectorAll ("#preview");
preview[0].setAttribute("data", link);
