jQuery and .length>0

var sd = jQuery(".bla");
if (sd.length>0){

}

Is there any cooler way to write that code? I want some code to execute only if there are some classes named bla. I do know I can use the each, b开发者_如何学JAVAut I do not want to and I do know I can do stuff like sd.action(), but I do not want to.

I'm not sure how much 'cooler' this is, but just:

if ($('.bla').length) {
    // Do stuff
}

Will do the trick.

Edit: If you need to re-use the selector after the check, you can still use the same syntax:

var sd = $(".bla");

if (sd.length) {
    // Do stuff
}

To make the code look a little "cooler" if you don't want to use length etc..

jQuery.fn.extend({
    exists: function() {
      return this.length !== 0;
    }
});

if (jQuery(".bla").exists()) {
  console.log('found');
}

Honestly, this is a perfectly acceptable and fast way (no function calls) to do what you want. I do similar things all the time. Even using $().each is a little slower because it requires a function call, even though it won't actually do anything.

Regarding the other answer here, which is also correct: Doing $('.bla') more than once will also be slower. If you think you may use $('.bla') later, it's better to store it in a variable like you have in your code. This avoids another jQuery call and lets the browser take care of the garbage collection.

Hope this makes sense! :)

The "coolest" way to make that look (in my opinion) is

if ( $('.bla').length > 0 ) {
    // ...
}

You can use .size()

$(".blah").size() > 0

http://api.jquery.com/size/

Nope.

I dont think there is anything cooler. (SO wouldnt let me just answer the question with No )