How to get a div with multiple classes count using jQuery

I have a sample HTML like the following,

<div class="class1"></div>
<div class="class2 class3"></div>

And my JS is,

alert(jQuery(".class1").length);
alert(jQuery(".class2 class3").length);

For the first alert I am getting 1 as expected, but I am getting 0 for the second alert. How to get the value 1 for the second alert as 开发者_如何学Cwell. I need specifically this case (where a div has both class2 and class3). Help me.

Thanks

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You want '.class2.class3'

What you have ('.class2 class3') means "A <class3> element that is a descendent of an element that is a member of class2".

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Take out the space and you're missing a dot, the selector you're looking for is $('.class2.class3')

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('.class2 class3') has no meaning.

('.class2 .class3') : an element with class3 which is a child of an element with class2 .
('.class2.class3'): an element which has class2 AND class3, both.