jQuery function not binding to newly added dom elements

问题

Here's index.html:

<head>
  <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js"></script>
  <script type="text/javascript">

    $(document).ready(function() {
      $('.btn_test').click(function() { alert('test'); });
    });

    function add(){
      $('body').append('<a href=\'javascript:;\' class=\'btn_test\'>test</a>');
    }

  </script>
</head>
<body>
  <a href="javascript:;" class="btn_test">test1</a>
  <a href="javascript:;" onclick="add()">add</a>
</body>

If I click on test1 link, it shows alert('test'), but if I click on add link then click on test, it doesn't show anything.

Could you explain it?

回答1:

For users coming to this question after 2011, there is a new proper way to do this:

$(document).on('click', '.btn_test', function() { alert('test'); });

This is as of jQuery 1.7.

For more information, see Direct and delegated events

回答2:

You need to use a "live" click listener because initially only the single element will exist.

$('.btn_test').live("click", function() { 
   alert('test'); 
});

Update: Since live is deprecated, you should use "on()":

$(".btn_test").on("click", function(){ 
   alert("test");
});

http://api.jquery.com/on/

回答3:

I have same problem like question I was just near to pulling my hair then i got the solution. I was using different syntax

$(".innerImage").on("click", function(){ 
alert("test");
});

it was not working for me (innerImage is dynamically created dom) Now I'm using

$(document).on('click', '.innerImage', function() { alert('test'); });

http://jsfiddle.net/SDJEp/2/

thanks @Moshe Katz

回答4:

.click binds to what is presently visible to jQuery. You need to use .live:

$('.btn_test').live('click', function() { alert('test'); });

回答5:

Use Jquery live instead. Here is the help page for it http://api.jquery.com/live/

$('.btn_test').live(function() { alert('test'); });

Edit: live() is deprecated and you should use on() instead.

$(".btn_test").on("click", function(){ 
   alert("test");
});

回答6:

This is because you click event is only bound to the existing element at the time of binding. You need to use live or delegate which will bind the event to existing and future elements on the page.

$('.btn_test').live("click", function() { alert('test'); });

Jquery Live

回答7:

you need live listener instead of click:

$('.btn_test').live('click', function() { 
   alert('test'); 
});

The reason being is that the click only assigns the listener to elements when the page is loading. Any new elements added will not have this listener on them. Live adds the click listener to element when the page loads and when they are added afterwards

回答8:

When the document loads you add event listeners to each matching class to listen for the click event on those elements. The same listener is not automatically added to elements that you add to the Dom later.

回答9:

Because the event is tied to each matching element in the document ready. Any new elements added do NOT automatically have the same events tied to them.

You will have to manually bind the event to any new element, after it is added, or use the live listener.

回答10:

$('.btn_test').click

will add the handler for elements which are available on the page (at this point 'test' does not exist!)

you have to either manually add a click handler for this element when you do append, or use a live event handler which will work for every element even if you create it later..

$('.btn_test').live(function() { alert('test'); });

回答11:

After jquery 1.7 on method can be used and it really works nice

<!DOCTYPE html>
<html>
<head>
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.1/jquery.min.js">
    </script>
<script>
    $(document).ready(function(){
      $("p").on("click",function(){
       alert("The paragraph was clicked.");
       $("body").append("<p id='new'>Now click on this paragraph</p>");
    });
    $(document).on("click","#new",function(){
       alert("On really works.");
      });
    });
</script>
</head>
<body>
    <p>Click this paragraph.</p>
</body>
</html>

see it in action http://jsfiddle.net/rahulchaturvedie/CzR6n/

回答12:

Or just run the script at the end of your page

回答13:

You need to add a proper button click function to give a proper result

$("#btn1").live(function() { alert("test"); });

来源：https://stackoverflow.com/questions/6537323/jquery-function-not-binding-to-newly-added-dom-elements

标签

javascript

jquery

onclick