Jquery常用技巧收集整理篇

比如有禁止右键点击、隐藏搜索文本框文字、在新窗口中打开链接、检测浏览器、预加载图片等等。具体如下：
禁止右键点击

$(document).ready(function(){ 
$(document).bind("contextmenu",function(e){ 
return false; 
}); 
});

隐藏搜索文本框文字

$(document).ready(function() { 
$("input.text1").val("Enter your search text here"); 
textFill($('input.text1')); 
}); 
function textFill(input){ //input focus text function 
var originalvalue = input.val(); 
input.focus( function(){ 
if( $.trim(input.val()) == originalvalue ){ input.val(''); } 
}); 
input.blur( function(){ 
if( $.trim(input.val()) == '' ){ input.val(originalvalue); } 
}); 
}

在新窗口中打开链接

$(document).ready(function() { 
//Example 1: Every link will open in a new window 
$('a[href^="http://"]').attr("target", "_blank"); 
//Example 2: Links with the rel="external" attribute will only open in a new window 
$('a[@rel$='external']').click(function(){ 
this.target = "_blank"; 
}); 
}); 
// how to use 
<A href="http://www.opensourcehunter.com" rel=external>open link</A>

检测浏览器
注: 在版本jQuery 1.4中，$.support 替换掉了$.browser 变量。

$(document).ready(function() { 
// Target Firefox 2 and above 
if ($.browser.mozilla && $.browser.version >= "1.8" ){ 
// do something 
} 
// Target Safari 
if( $.browser.safari ){ 
// do something 
} 
// Target Chrome 
if( $.browser.chrome){ 
// do something 
} 
// Target Camino 
if( $.browser.camino){ 
// do something 
} 
// Target Opera 
if( $.browser.opera){ 
// do something 
} 
// Target IE6 and below 
if ($.browser.msie && $.browser.version <= 6 ){ 
// do something 
} 
// Target anything above IE6 
if ($.browser.msie && $.browser.version > 6){ 
// do something 
} 
});

预加载图片

$(document).ready(function() { 
jQuery.preloadImages = function() 
{ 
for(var i = 0; i").attr("src", arguments[i]); 
} 
}; 
// how to use 
$.preloadImages("image1.jpg"); 
});

页面样式切换

$(document).ready(function() { 
$("a.Styleswitcher").click(function() { 
//swicth the LINK REL attribute with the value in A REL attribute 
$('link[rel=stylesheet]').attr('href' , $(this).attr('rel')); 
}); 
// how to use 
// place this in your header 
<LINK href="default.css" type=text/css rel=stylesheet> 
// the links 
<A class=Styleswitcher href="#" rel=default.css>Default Theme</A> 
<A class=Styleswitcher href="#" rel=red.css>Red Theme</A> 
<A class=Styleswitcher href="#" rel=blue.css>Blue Theme</A> 
});

列高度相同
如果使用了两个CSS列，使用此种方式可以是两列的高度相同。

$(document).ready(function() { 
function equalHeight(group) { 
tallest = 0; 
group.each(function() { 
thisHeight = $(this).height(); 
if(thisHeight > tallest) { 
tallest = thisHeight; 
} 
}); 
group.height(tallest); 
} 
// how to use 
$(document).ready(function() { 
equalHeight($(".left")); 
equalHeight($(".right")); 
}); 
});

动态控制页面字体大小

$(document).ready(function() { 
// Reset the font size(back to default) 
var originalFontSize = $('html').css('font-size'); 
$(".resetFont").click(function(){ 
$('html').css('font-size', originalFontSize); 
}); 
// Increase the font size(bigger font0 
$(".increaseFont").click(function(){ 
var currentFontSize = $('html').css('font-size'); 
var currentFontSizeNum = parseFloat(currentFontSize, 10); 
var newFontSize = currentFontSizeNum*1.2; 
$('html').css('font-size', newFontSize); 
return false; 
}); 
// Decrease the font size(smaller font) 
$(".decreaseFont").click(function(){ 
var currentFontSize = $('html').css('font-size'); 
var currentFontSizeNum = parseFloat(currentFontSize, 10); 
var newFontSize = currentFontSizeNum*0.8; 
$('html').css('font-size', newFontSize); 
return false; 
}); 
});

返回页面顶部功能

$(document).ready(function() { 
$('a[href*=#]').click(function() { 
if (location.pathname.replace(/^\//,'') == this.pathname.replace(/^\//,'') 
&& location.hostname == this.hostname) { 
var $target = $(this.hash); 
$target = $target.length && $target 
|| $('[name=' + this.hash.slice(1) +']'); 
if ($target.length) { 
var targetOffset = $target.offset().top; 
$('html,body') 
.animate({scrollTop: targetOffset}, 900); 
return false; 
} 
} 
}); 
// how to use 
// place this where you want to scroll to 
<A name=top></A> 
// the link 
<A href="#top">go to top</A> 
});

获得鼠标指针XY值

$(document).ready(function() { 
$().mousemove(function(e){ 
//display the x and y axis values inside the div with the id XY 
$('#XY').html("X Axis : " + e.pageX + " | Y Axis " + e.pageY); 
}); 
// how to use 
<DIV id=XY></DIV> 
});

验证元素是否为空

$(document).ready(function() { 
if ($('#id').html()) { 
// do something 
} 
});

替换元素

$(document).ready(function() { 
$('#id').replaceWith(' 
<DIV>I have been replaced</DIV> 
); 
});

jQuery延时加载功能

$(document).ready(function() { 
window.setTimeout(function() { 
// do something 
}, 1000); 
});

移除单词功能

$(document).ready(function() { 
var el = $('#id'); 
el.html(el.html().replace(/word/ig, "")); 
});

验证元素是否存在于jQuery对象集合中

$(document).ready(function() { 
if ($('#id').length) { 
// do something 
} 
});

使整个DIV可点击

$(document).ready(function() { 
$("div").click(function(){ 
//get the url from href attribute and launch the url 
window.location=$(this).find("a").attr("href"); return false; 
}); 
// how to use 
<DIV><A href="index.html">home</A></DIV> 
});

ID与Class之间转换当改变Window大小时，在ID与Class之间切换

$(document).ready(function() { 
function checkWindowSize() { 
if ( $(window).width() > 1200 ) { 
$('body').addClass('large'); 
} 
else { 
$('body').removeClass('large'); 
} 
} 
$(window).resize(checkWindowSize); 
});

克隆对象

$(document).ready(function() { 
var cloned = $('#id').clone(); 
// how to use 
<DIV idid=id></DIV> 
});

使元素居屏幕中间位置

$(document).ready(function() { 
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; 
} 
$("#id").center(); 
});

写自己的选择器

$(document).ready(function() { 
$.extend($.expr[':'], { 
moreThen1000px: function(a) { 
return $(a).width() > 1000; 
} 
}); 
$('.box:moreThen1000px').click(function() { 
// creating a simple js alert box 
alert('The element that you have clicked is over 1000 pixels wide'); 
}); 
});

统计元素个数

$(document).ready(function() { 
$("p").size(); 
});

使用自己的Bullets

$(document).ready(function() { 
$("ul").addClass("Replaced"); 
$("ul > li").prepend("‒ "); 
// how to use 
ul.Replaced { list-style : none; } 
});

引用Google主机上的jQuery类库

//Example 1 
<SCRIPT src="http://www.google.com/jsapi"></SCRIPT> 
<SCRIPT type=text/javascript> 
google.load("jquery", "1.2.6"); 
google.setOnLoadCallback(function() { 
// do something 
}); 
</SCRIPT><SCRIPT src="http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js" type=text/javascript></SCRIPT> 
// Example 2:(the best and fastest way) 
<SCRIPT src="http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js" type=text/javascript></SCRIPT>

禁用jQuery（动画）效果

$(document).ready(function() { 
jQuery.fx.off = true; 
});

与其他JavaScript类库冲突解决方案

$(document).ready(function() { 
var $jq = jQuery.noConflict(); 
$jq('#id').show(); 
});