Detailed explanation of $(function() {}); in jQuery

Detailed explanation of $(function() {}); in jQuery_jquery

WBOY

Release： 2016-05-16 15:46:10

Original

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The code in $(document).ready() is executed after the page content is loaded. If the code is written directly into the script tag, the code inside the script tag will be executed when the page is loaded. At this time, if the code executed in your tag calls code or DOM that has not yet been loaded, an error will be reported. Of course, if you put the script tag at the end of the page, there will be no problem. The effect is the same as ready.

$(document).ready(function(){}) can be abbreviated as $(function(){});

After clicking on the paragraph, this paragraph is hidden:

<html>
<head>
<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js" type="text/javascript"></script>
<script type="text/javascript">
$(document).ready(function(){
 $("p").click(function(){
  $(this).hide();
 });
});
</script>
</head>

<body>
 <p>If you click on me, I will disappear.</p>
</body>
</html>

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If $(document).ready(function() {}); is removed, the paragraph cannot be hidden:

<html>
<head>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript">
 $("p").click(function(){
  $(this).hide();
 });
</script>
</head>

<body>
 <p>If you click on me, I will disappear.</p>
</body>
</html>

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But if you put the script at the end of the page, the hidden effect can be restored:

<html>
<head>
</head>

<body>
 <p>If you click on me, I will disappear.</p>
</body>

<script type="text/javascript" src="jquery-1.7.2.min.js"></script>
<script type="text/javascript">
 $("p").click(function(){
   $(this).hide();
 });
</script>
</html>

Copy after login

Summary:

The code in $(document).ready is executed after the page content is loaded. You write it directly into the script tag. When the page is loaded, the script tag will execute the code inside. If you If the executed code calls code or DOM that has not been loaded yet, an error will be reported,
Of course, if you put the script tag at the end of the page, then there will be no problem and the effect will be similar to ready