26个Jquery使用小技巧

下面列出了一些Jquery使用技巧。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、页面样式切换、所有列等高、动态控制页面字体大小、获得鼠标指针的X值Y值、验证元素是否为空、替换元素、延迟加载、验证元素是否存在于Jquery集合中、使DIV可点击、克隆对象、使元素居中、计算元素个数、使用Google主机上的Jquery类库、禁用Jquery效果、解决Jquery类库与其他Javascript类库冲突问题。

1. 禁止右键点击

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$(document).ready(function(){

$(document).bind("contextmenu",function(e){

returnfalse;

});

});

2. 隐藏搜索文本框文字

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$(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); }

});

}

3. 在新窗口中打开链接

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$(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.cdtarena.com" rel=external>open link</A>

4. 检测浏览器

注: 在版本jQuery 1.4中，$.support 替换掉了$.browser 变量

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$(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

}

});

5. 预加载图片

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$(document).ready(function(){

jQuery.preloadImages = function()

{

for(var i = 0; i<ARGUMENTS.LENGTH; jQuery(?<img { i++)>").attr("src", arguments[i]);

}

}

// how to use

$.preloadImages("image1.jpg");

});

6. 页面样式切换

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$(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 rel=stylesheet type=text/css href="default.css">

// 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>

});

7. 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。

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$(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"));

});

});

8. 动态控制页面字体大小

用户可以改变页面字体大小

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$(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);

returnfalse; });

// 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);

returnfalse;

});

});

9. 返回页面顶部功能

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$(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);

returnfalse;

}

}

});

// how to use

// place this where you want to scroll to

<A name=top></A>

// the link

<A href="#top">go to top</A>

});

11. 获得鼠标指针ＸＹ值

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$(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>

});

12. 验证元素是否为空

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$(document).ready(function() {

if ($('#id').html()) {

// do something

}

});

13. 替换元素

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$(document).ready(function() {

$('#id').replaceWith('

<DIV>I have been replaced</DIV>

');

});

14. jQuery延时加载功能

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$(document).ready(function() {

window.setTimeout(function() {

// do something

}, 1000);

});

15. 移除单词功能

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$(document).ready(function() {

var el = $('#id');

el.html(el.html().replace(/word/ig, ""));

});

16. 验证元素是否存在于jquery对象集合中

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$(document).ready(function() {

if ($('#id').length) {

// do something

}

});

17. 使整个DIV可点击

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$(document).ready(function() {

$("div").click(function(){

//get the url from href attribute and launch the url

window.location=$(this).find("a").attr("href"); returnfalse;

});

// how to use

<DIV><A href="index.html">home</A></DIV>

});

18. ID与Class之间转换.

当改变Window大小时，在ID与Class之间切换

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$(document).ready(function() {

function checkWindowSize() {

if ( $(window).width() > 1200 ) {

$('body').addClass('large');

}

else {

$('body').removeClass('large');

}

}

$(window).resize(checkWindowSize);

});

19. 克隆对象

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$(document).ready(function() {

var cloned = $('#id').clone();

// how to use

<DIV id=id></DIV>

});

20. 使元素居屏幕中间位置

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$(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");

returnthis;

}

$("#id").center();

});

21. 写自己的选择器

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$(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');

});

});

22. 统计元素个数

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$(document).ready(function() {

$("p").size();

});

23. 使用自己的 Bullets

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$(document).ready(function() {

$("ul").addClass("Replaced");

$("ul > li").prepend("‒ ");

// how to use

ul.Replaced { list-style : none; }

});

24. 引用Google主机上的Jquery类库

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//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 type=text/javascript src="http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js"></SCRIPT>

// Example 2:(the best and fastest way)

<SCRIPT type=text/javascript src="http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js"></SCRIPT>

25. 禁用Jquery（动画）效果

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$(document).ready(function() {

jQuery.fx.off = true;

});

26. 与其他Javascript类库冲突解决方案

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$(document).ready(function() {

var $jq = jQuery.noConflict();

$jq('#id').show();

});

转自：http://www.cdtarena.com/javapx/201303/8010.html