Select first and last element with particular class using jQuery

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执笔经年
执笔经年 2020-12-16 10:08

I have a list of spans with particular class \"place\" and some of them have class \"activated\". Is there a way to select the first item with class \"activated\" and the la

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  • var first = $('.activated:first');
    var last = $('.activated:last');
    
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  • 2020-12-16 10:42
    var firstspan = $('span.activated:first'),
        lastspan = $('span.activated:last');
    

    By the way, if you're using jQuery, what's with all the inline click events?

    You could add some code like so:

    $('span.place').click(function() {
        activate(); // you can add `this` as a parameter
                    // to activate if you need scope.
    });
    
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  • 2020-12-16 10:42

    If you take care about performance, than better use $('span.place.activated') instead $('.activated:first'). But, in this case, the second variant correct too.

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  • 2020-12-16 10:49
    var places = $('span.place.activated');
    
    var first = places.first(),
        last  = places.last();
    

    Explanation: The span.places.activated selector will get all <span>s with both "place" and "activated" classes. Then the first() and last() methods will return the first and last items of that set. This is preferable to using the :first and :last pseudoselectors because selection is expensive and this way we only do selection once and then rely on (cheap) array operations to get the first and last elements.

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