JQuery and .length>0

coding-stylejquery

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, but I do not want to and I do know I can do stuff like sd.action(), but I do not want to.

Best Answer

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
}

Related Solutions

Javascript – How to check if an element is hidden in jQuery

Since the question refers to a single element, this code might be more suitable:

// Checks CSS content for display:[none|block], ignores visibility:[true|false]
$(element).is(":visible");

// The same works with hidden
$(element).is(":hidden");

It is the same as twernt's suggestion, but applied to a single element; and it matches the algorithm recommended in the jQuery FAQ.

We use jQuery's is() to check the selected element with another element, selector or any jQuery object. This method traverses along the DOM elements to find a match, which satisfies the passed parameter. It will return true if there is a match, otherwise return false.

Jquery – How to format a Microsoft JSON date

eval() is not necessary. This will work fine:

var date = new Date(parseInt(jsonDate.substr(6)));

The substr() function takes out the /Date( part, and the parseInt() function gets the integer and ignores the )/ at the end. The resulting number is passed into the Date constructor.

I have intentionally left out the radix (the 2nd argument to parseInt); see my comment below.

Also, I completely agree with Rory's comment: ISO-8601 dates are preferred over this old format - so this format generally shouldn't be used for new development.

For ISO-8601 formatted JSON dates, just pass the string into the Date constructor:

var date = new Date(jsonDate); //no ugly parsing needed; full timezone support

Best Answer

Related Solutions

Javascript – How to check if an element is hidden in jQuery

Jquery – How to format a Microsoft JSON date

Related Topic