jQuery 如何检查元素是否没有特定的类？
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How to check if an element does NOT have a specific class?
提问by user1005793
How do I check if there isn't a class. For example, I know how to check to see if it has the class "test", but how do I check to see if it doesn't have the class "test"?
我如何检查是否有课程。例如，我知道如何检查它是否有“test”类，但是如何检查它是否没有“test”类？
if($(this).hasClass("test")){
}
回答by sdleihssirhc
if (!$(this).hasClass("test")) {
回答by JJJ
sdleihssirhc's answer is of course the correct one for the case in the question, but just as a reference if you need to select elements that don't have a certain class, you can use the notselector:
sdleihssirhc 的答案当然是问题中案例的正确答案，但作为参考，如果您需要选择没有特定类的元素，您可以使用not选择器：
// select all divs that don't have class test
$( 'div' ).not( ".test" );
$( 'div:not(.test)' ); // <-- alternative
回答by George-Paul B.
Select element (or group of elements) having class "abc", not having class "xyz":
选择具有类“abc”而不具有类“xyz”的元素（或元素组）：
$('.abc:not(".xyz")')
When selecting regular CSS you can use .abc:not(.xyz).
选择常规 CSS 时，您可以使用.abc:not(.xyz).
回答by Matthew Cira
use the .not() method and check for an attribute:
使用 .not() 方法并检查属性：
$('p').not('[class]');
Check it here: http://jsfiddle.net/AWb79/
在这里检查：http: //jsfiddle.net/AWb79/
回答by aircraft
You can try this:
你可以试试这个：
<div id="div1" class="myClass">there is a class</div>
<div id="div2"> there is no class2 </div>
$(document).ready(function(){
$("#div2").not('.myClass'); // do not have `myClass` class.
});
回答by Aljo?a
I don't know why, but the accepted answer didn't work for me. Instead this worked:
我不知道为什么，但接受的答案对我不起作用。相反，这有效：
if ($(this).hasClass("test") !== false) {}
回答by omarjebari
There are more complex scenarios where this doesn't work. What if you want to select an element with class A that doesn't contain elements with class B. You end up needing something more like:
还有更复杂的场景，这不起作用。如果你想选择一个不包含类 B 元素的 A 类元素怎么办。你最终需要更多类似的东西：
If parent element does not contain certain child element; jQuery
回答by le_pragmatist
reading through this 6yrs later and thought I'd also take a hack at it, also in the TIMTOWTDI vein...:D, hoping it isn't incorrect 'JS etiquette'.
6 年后通读这篇文章，并认为我也会对它进行黑客攻击，也是在TIMTOWTDI 静脉中......：D，希望它不是不正确的“JS 礼仪”。
I usually set up a var with the condition and then refer to it later on..i.e;
我通常设置一个带有条件的变量，然后稍后再参考它..ie;
// var set up globally OR locally depending on your requirements
var hC;
function(el) {
var $this = el;
hC = $this.hasClass("test");
// use the variable in the conditional statement
if (!hC) {
//
}
}
Although I should mention that I do this because I mainly use the conditional ternary operator and want clean code. So in this case, all i'd have is this:
虽然我应该提到我这样做是因为我主要使用条件三元运算符并且想要干净的代码。所以在这种情况下，我所拥有的就是：
hC ? '' : foo(x, n) ;
// OR -----------
!hC ? foo(x, n) : '' ;
...instead of this:
...而不是这个：
$this.hasClass("test") ? '' : foo(x, n) ;
// OR -----------
(!$this.hasClass("test")) ? foo(x, n) : '' ;
