25個實用的jQuery技巧和解決方案

1. 去除頁面的右鍵菜單
$(document).ready(function(){ $(document).bind(“contextmenu”,function(e){returnfalse;});});

2、搜索輸入框文字的消失
當鼠標獲得焦點、失去焦點的時候，input輸入框文字處理：
$(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、新窗口打開頁面
$(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>

4、判斷瀏覽器類型
注意： jQuery 1.4中$.support 來代替以前的$.browser
$(document).ready(function(){// Target Firefox 2 and above if($.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、預加載圖片
$(document).ready(function(){ jQuery.preloadImages=function(){for(var i =0; i<arguments.length; i++)=”"{=”" jquery(“=”"><img>”).attr(“src”, arguments);}}// how to use $.preloadImages(“image1.jpg”);});</arguments.length;>

6、輕鬆切換css樣式
$(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” href=”default.css” type=”text/css”> // the links <a href=”#” rel=”default.css”>Default Theme</a> <a href=”#” class=”Styleswitcher” rel=”red.css”>Red Theme</a> <a href=”#” class=”Styleswitcher” rel=”blue.css”>Blue Theme</a> });

7、高度相等的列
如果您使用兩個CSS列，以此來作爲他們完全一樣的高度
$(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、簡單字體變大縮小
$(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);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、返回頭部滑動動畫
$(‘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>

10、獲取鼠標位置
$().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);});

11、判斷一個元素是否爲空
if($(‘#id’).html()){// do something }

12、替換元素
$(‘#id’).replaceWith(‘ <div>I have been replaced</div> ‘);

13、jquery timer 返回函數
$(document).ready(function(){ window.setTimeout(function(){// do something },1000);});

14、jquery也玩替換
$(document).ready(function(){var el = $(‘#id’); el.html(el.html().replace(/word/ig,”"));});

15、判斷元素是否存在
$(document).ready(function(){if($(‘#id’).length){// do something }});

16、讓div也可以click
$(“div”).click(function(){//get the url from href attribute and launch the url window.location=$(this).find(“a”).attr(“href”);returnfalse;});
// how to use
<div><a href=”index.html”>home</a></div>

17、使用jquery來判斷瀏覽器大小添加不同的class
$(document).ready(function(){function checkWindowSize(){if( $(window).width()>1200){ $(‘body’).addClass(‘large’);}else{ $(‘body’).removeClass(‘large’);}} $(window).resize(checkWindowSize);});

18、幾個字符就clone！
var cloned = $(‘#id’).clone()

19、設置div在屏幕中央
$(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();});

20、創建自己的選擇器
$(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’);});});

21、計算元素的數目
$(document).ready(function(){ $(“p”).size();});

22、設置自己的li樣式
$(document).ready(function(){ $(“ul”).addClass(“Replaced”); $(“ul > li”).prepend(“‒ “);// how to use ul.Replaced{ list-style : none;}});

23、使用google的主機來加載jquery庫
<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 2the best and fastest way) <script type=”text/javascript” src=”http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js”></script>

24、關閉jquery動畫效果
$(document).ready(function(){ jQuery.fx.off=true;});

25、使用自己的jquery標識
$(document).ready(function(){var $jq = jQuery.noConflict(); $jq(‘#id’).show();});