Using !important in jQuery's css() function

问题

I have a dialog with an overlay declared like so:

     .ui-widget-overlay  {
         position: absolute;
         left: 8px;
         top: 9px;
         height: 985px !important;
         width: 518px !important; 
      }

The page I have will have two different page heights. To account for this with the overlay I have done this in my JS file:

If small one visible:

$('.ui-widget-overlay').css("height", "985px !important");

else

$('.ui-widget-overlay').css("height", "1167px !important");

Apparently this does not work. Is there another way to over ride !important that would?

The page can switch back and forth so I need to always have one or the other. Also if I do not add !important to the css then the overlay will expand in height infinitely (its in facebook so i am assuming there is an issue there)

Any suggestions?

回答1:

Dont apply styles to a class. Apply a class to your div as a style!

Let jQuery do all the work for you

You style sheet should have these classes in them

.ui-widget-overlay  {
         position: absolute;
         left: 8px;
         top: 9px;
         width: 518px !important; 
         }

.ui-widget-small { height: 985px;  }

.ui-widget-full { height: 1167px; }

Ok thats your CSS sorted

now your div

 <div id="myWidget" class="ui-widget-overlay ui-widget-small"> YOUR STUFF </div>

Now you can use jQuery to manipulate your divs either by attaching to a button/click/hover whatever it is you wanna use

$('#myWidget').removeClass('ui-widget-small').addClass('ui-widget-full')

And you dont need to use !important - that is really used when you start having issues with large CSS files or several loaded styles.

This is instant but you can also add an effect

$('#myWidget').hide('slow', function(){ $('#myWidget').removeClass('ui-widget-small').addClass('ui-widget-full').show('slow') }  )

You can add styles dynamically to your page like this- and to replace all existing classes with another class, we can use .attr('class', 'newClass') instead.

$('body').prepend('<style type="text/css"> .myDynamicWidget { height: 450px; } </style>')
$('#myWidget').attr('class', 'ui-widget-overlay')
$('#myWidget').addClass('myDynamicWidget')

But you do not want to be over writing your existing styles using this method. This should be used in a 'lost' case scenario. Just demonstrates the power of jQuery

回答2:

There is a trick to do this.

$('.ui-widget-overlay').css('cssText', 'height:985px !important;');

$('.ui-widget-overlay').css('cssText', 'height:1167px !important;');

cssText is doing the trick here. It is appending css styles as string, not as variable.

回答3:

You could try using $(this).attr('style', 'height:1167px !important'); I haven't tested it, but it should work.

回答4:

You can create a dynamic stylesheet with rules that override the properties you want and apply it on the page.

var $stylesheet = $('<style type="text/css" media="screen" />');

$stylesheet.html('.tall{height:1167px !important;} .short{height:985px !important}');

$('body').append($stylesheet);

Now, when you add our newly created classes, they will take precedence since they are the last defined.

$('.ui-widget-overlay').addClass('tall');

demo at http://jsfiddle.net/gaby/qvRSs/

---

update

For pre-IE9 support use

var $stylesheet = $('<style type="text/css" media="screen">\
                    .tall{height:300px !important;}\
                    .short{height:100px !important}\
                    </style>');

$('body').append($stylesheet);

demo at http://jsfiddle.net/gaby/qvRSs/3/

回答5:

Unless I've misread your question, what you're doing does work in jsfiddle.

EDIT: My fiddle only works in some browsers (so far, Chrome: pass, IE8: fail).

回答6:

I solved this problem like this:

inputObj.css('cssText', inputObj.attr('style')+'padding-left: ' + (width + 5) + 'px !IMPORTANT;');

So no inline-Style is lost, an the last overrides the first

回答7:

Please remove height attribute from class and then try to implement your if and else condition.

.ui-widget-overlay  {
         position: absolute;
         left: 8px;
         top: 9px;
         width: 518px !important; 
         }

if
     $('.ui-widget-overlay').attr("height", "985px");
else
     $('.ui-widget-overlay').attr("height", "1167px");

Enjoy code....keep smiling...

来源：https://stackoverflow.com/questions/5824079/using-important-in-jquerys-css-function