向DOM元素添加变量

Question

I would like to ask, if is 'legal' to add custom variables to document body elements. 我想问一下，如果将“自定义变量”添加到文档正文元素是“合法的”。 For example: 例如：

document.getElementById('elem1').customVariable = 'xxx';

This code just work, but i don't know if it is 'allowed' 这段代码正常工作，但我不知道它是否“允许”

It doesn't appear in list of tag's arguments, but variable is usable in further code.. 它不会出现在标记参数列表中，但变量可用于更多代码中。

Answer 1

I think that will work, but the more common way to add custom attribute is like this: 我认为这会有效，但更常见的添加自定义属性的方法是这样的：

<div id="elem1" data-customVariable="foo"

And then 然后

document.getElementById('elem1').setAttribute("data-customVariable", "bar");

Or if older browser choke on setAttribute 或者如果旧的浏览器在setAttribute阻塞

document.getElementById('elem1')["data-customVariable"] ="bar";

EDIT 编辑

Thanks to pimvdb for pointing out that you can also do 感谢pimvdb指出你也可以做到

document.getElementById('elem1').dataset.customVariable ="bar";

Just note that you'll have to watch how you name this -- the camel casing can throw it off. 请注意，你必须注意你的名字 - 骆驼外壳可以把它扔掉。 You'll want 你想要的

<div id="elem1" data-custom-variable="xxx"></div>