jQuery blur() not working?

问题

Totally stumped here. Trying something pretty easy, but it's not working:

$("input.input1, textarea.input1").focus(function(){
    $(this).addClass("input2").removeClass("input1");
});
$("input.input2, textarea.input2").blur(function(){
    $(this).addClass("input1").removeClass("input2");
});

Basically the blur isn't firing. I click on the input box and the box changes. I click away from the box and nothing happens. Any help with this would be awesome.

回答1:

You need to use a delegated handler as the input doesn't have class input2 at the time the handler is applied.

$(document).on('focus','input.input1, textarea.input1', function() {
    $(this).addClass('input2').removeClass('input1');
});
$(document).on('blur','input.input2, textarea.input2', function() {
    $(this).addClass('input1').removeClass('input2');
});

There are probably better ways to do this, however. I'd suggest using a third class to mark the inputs that need the class toggled, then just toggle the classes when the event occurs.

$('.needsToggle').on('focus blur', function() {
     $(this).toggleClass('input1 input2');
});

If they always have class input1 to start, you could use that instead of needsToggle.

回答2:

Because you're affecting the same elements, it's somewhat easier to chain:

$("input.input1, textarea.input1").focus(function(){
    $(this).addClass("input2").removeClass("input1");
}).blur(function(){
    $(this).addClass("input1").removeClass("input2");
});

JS Fiddle demo.

As to why your jQuery isn't working as-is, I'm unsure, I'm afraid; though I suspect it's to do with the selectors.

回答3:

Try this code:

$("input.input1, textarea.input1").bind('focus blur', function(){
    $(this).toggleClass("input2").toggleClass("input1");
});

If it does not work, you might need to use focusout instead of blur:

$("input.input1, textarea.input1").bind('focus focusout', function(){
    $(this).toggleClass("input2").toggleClass("input1");
});

回答4:

You need to use .delegate() if you are on jQuery < 1.7.

And .on() if you are on 1.7 or greater.

Don't use .live() since it is waaaaay slower.

回答5:

Also if your elements loaded with ajax use $(document).on(event,selector,function) , because standart eg. $(selector).click(function() ... will not work

来源：https://stackoverflow.com/questions/8290180/jquery-blur-not-working

标签

jquery

blur