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I'm very new to jQuery BUT I've got the basics down... At least I think I do? I'm just not sure how to put them together for them to actually work.

Example:
IF (div with ID of #dynamicChat) is present on the page. Then (div with class of .prdSection) height is 25px. Else do nothing

What I have so far:

$('#dynamicChat'){
$('.prdSection').css('height', '25px');
}

I don't think I'm far off... Saying that I probably am :) Any help would be great!

*Side question - If I'm referring to a Div on a page, what would I call it? An Element?

Thanks :)

I'm very new to jQuery BUT I've got the basics down... At least I think I do? I'm just not sure how to put them together for them to actually work.

Example:
IF (div with ID of #dynamicChat) is present on the page. Then (div with class of .prdSection) height is 25px. Else do nothing

What I have so far:

$('#dynamicChat'){
$('.prdSection').css('height', '25px');
}

I don't think I'm far off... Saying that I probably am :) Any help would be great!

*Side question - If I'm referring to a Div on a page, what would I call it? An Element?

Thanks :)

• javascript
• jquery
• html
• css

Share Improve this question Follow asked Mar 14, 2014 at 19:46 NickNick 2,55955 gold badges3939 silver badges7272 bronze badges 3

• you can always check the .length of a jq query to see if it is >0 – jumpdart Commented Mar 14, 2014 at 19:48
• possible duplicate of Check if element exists in jQuery – aksu Commented Mar 14, 2014 at 19:55
• Not sure how you would consider this a duplicate – Nick Commented Mar 14, 2014 at 19:59

Add a ment  | 

4 Answers 4

Sorted by: Reset to default 9

if ($('#dynamicChat').length > 0) {
    $('.prdSection').css('height', '25px');
}

You don’t need the “> 0”, you can simply write:

if ( $('#myElement').length ) {
// it exists
}

if ( $('#dynamicChat').length ) {
$('.prdSection').css('height', '25px');
}

No need of jQuery to check if that element exist :

if(document.getElementById('dynamicChat')){
    $('.prdSection').css('height', '25px');
}

If (div with ID of #dynamicChat) is present on the page. Then (div with class of .prdSection) height is 25px, else do nothing

   <script type="text/javascript">
        if ($('#dynamicChat').is("visible")) {
            $('.prdSection').css('height', '25px');
        }
    </script>

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