【转】7个有用的jQuery代码片段

$(document).ready(function() {  
  $("a[href^=‘http‘]").attr(‘target‘,‘_blank‘);  
});

<div class="equalHeight" style="border:1px solid">  
 <p>First Line</p>  
 <p>Second Line</p>  
 <p>Third Line</p>  
</div>  
<div class="equalHeight" style="border:1px solid">  
 <p>Column Two</p>  
</div>  
<script src="http://apps.bdimg.com/libs/jquery/1.11.1/jquery.min.js"></script>  
<script>  
$(document).ready(function() {  
 equalHeight(‘.equalHeight‘);  
});  
//global variable, this will store the highest height value  
var maxHeight = 0;  
function equalHeight(col) {  
 //Get all the element with class = col  
 col = $(col);  
 //Loop all the col  
 col.each(function() {  
  //Store the highest value  
  if ($(this).height() > maxHeight) {  
   maxHeight = $(this).height();  
  }  
 });  
 //Set the height  
 col.height(maxHeight);  
}  
</script> 

jQuery.preloadImagesInWebPage = function() {  
     for (var ctr = 0; ctr & lt; arguments.length; ctr++) {  
      jQuery("").attr("src", arguments[ctr]);  
     }  
    }  
    // 使用方法：  
    $.preloadImages("image1.gif", "image2.gif", "image3.gif");  
    // 检查图片是否被加载  
    $(‘#imageObject‘).attr(‘src‘, ‘image1.gif‘).load(function() {  
     alert(‘The image has been loaded…‘);  
});  

$(document).ready(function() {  
 //catch the right-click context menu  
 $(document).bind("contextmenu", function(e) {  
  //warning prompt - optional  
  alert("No right-clicking!");  
  //delete the default context menu  
  return false;  
 });  
}); 

$(document).ready(function() {  
     window.setTimeout(function() {  
      // some code  
     }, 500);  
 });  

<div id="foo">  
 <div id="bar"></div>  
 <div id="baz">  
  <div id="biz"></div>  
  <span><span></span></span>  
 </div>  
</div>  
<script src="http://apps.bdimg.com/libs/jquery/1.11.1/jquery.min.js"></script>  
<script type="text/javascript">  
 //jQuery code to count child elements $("#foo > div").size()  
alert($("#foo > div").size())  
</script>

<div id="foo" style="width:200px;height: 200px;background: #ccc;"></div>  
<script src="http://apps.bdimg.com/libs/jquery/1.11.1/jquery.min.js"></script>  
    <script type="text/javascript">  
    jQuery.fn.center = function() {  
     this.css("position", "absolute");  
     this.css("top", ($(window).height() - this.height()) / 2 + $(window).scrollTop() + "px");  
     this.css("left", ($(window).width() - this.width()) / 2 + $(window).scrollLeft() + "px");  
     return this;  
    }  
    //Use the above function as:  
    $(‘#foo‘).center();  
</script>