jquery代码失效 jquery常用代码

1. 创建一个嵌套的过滤器

1. .filter(":not(:has(.selected))") //去掉所有不包含class为.selected的元素

2. 重用你的元素查询

1. var allItems = $("div.item");  
2. var keepList = $("div#container1 div.item"); 
3. <div>class names: 
4. $(formToLookAt + " input:checked").each(function() {     keepListkeepList = keepList.filter("." + $(this).attr("name")); });
5. </div>

3. 使用has()来判断一个元素是否包含特定的class或者元素

1. //jQuery 1.4.* includes support for the has method. This method will find  
2. //if a an element contains a certain other element class or whatever it is  
3. //you are looking for and do anything you want to them. 
4. $("input").has(".email").addClass("email_icon");

4. 使用jQuery切换样式

1. //Look for the media-type you wish to switch then set the href to your new style sheet  
2. $('link[media='screen']').attr('href', 'Alternative.css');

5. 限制选择的区域

1. //Where possible, pre-fix your class names with a tag name  
2. //so that jQuery doesn't have to spend more time searching  
3. //for the element you're after. Also remember that anything  
4. //you can do to be more specific about where the element is  
5. //on your page will cut down on execution/search times  
6. var in_stock = $('#shopping_cart_items input.is_in_stock');
 
1. <ul id="shopping_cart_items">  
2. <li>  
3. <input value="Item-X" name="item" class="is_in_stock" type="radio"> Item X</li>  
4. <li>  
5. <input value="Item-Y" name="item" class="3-5_days" type="radio"> Item Y</li>  
6. <li>  
7. <input value="Item-Z" name="item" class="unknown" type="radio"> Item Z</li>  
8. </ul>

6. 如何正确使用ToggleClass

1. //Toggle class allows you to add or remove a class  
2. //from an element depending on the presence of that  
3. //class. Where some developers would use:  
4. a.hasClass('blueButton') ? a.removeClass('blueButton') : a.addClass('blueButton');  
5. //toggleClass allows you to easily do this using  
6. a.toggleClass('blueButton');

7. 设置IE指定的功能

1. if ($.browser.msie) { // Internet Explorer is a sadist. }

8. 使用jQuery来替换一个元素

1. $('#thatdiv').replaceWith('fnuh');

9. 验证一个元素是否为空

1. if ($('#keks').html()) { //Nothing found ;}

10. 在无序的set中查找一个元素的索引

1. $("ul > li").click(function () {  
2.     var index = $(this).prevAll().length;  
3. });

11. 绑定一个函数到一个事件

1. $('#foo').bind('click', function() {  
2.   alert('User clicked on "foo."');  
3. });

12. 添加HTML到一个元素

1. $('#lal').append('sometext');

13. 创建元素时使用对象来定义属性

1. var e = $("", { href: "#", class: "a-class another-class", title: "..." });

14. 使用过滤器过滤多属性

1. //This precision-based approached can be useful when you use  
2. //lots of similar input elements which have different types  
3. var elements = $('#someid input[type=sometype][value=somevalue]').get();

15. 使用jQuery预加载图片

1. jQuery.preloadImages = function() { for(var i = 0; i').attr('src', arguments[i]); } };  
2. // Usage $.preloadImages('image1.gif', '/path/to/image2.png', 'some/image3.jpg');

16. 设置任何匹配一个选择器的事件处理程序

1. $('button.someClass').live('click', someFunction);
2.   //Note that in jQuery 1.4.2, the delegate and undelegate options have been
3.   //introduced to replace live as they offer better support for context
4.     //For example, in terms of a table where before you would use..
5.   // .live()
6.   $("table").each(function(){
7.     $("td", this).live("hover", function(){
8.     $(this).toggleClass("hover");
9.     });
10.   });
11.   //Now use..
12.   $("table").delegate("td", "hover", function(){
13.   $(this).toggleClass("hover");
14. });

17. 找到被选择到的选项(option)元素

1. $('#someElement').find('option:selected');

18. 隐藏包含特定值的元素

1. $("p.value:contains('thetextvalue')").hide();

19. 自动的滚动到页面特定区域

1. jQuery.fn.autoscroll = function(selector) {
2.   $('html,body').animate(
3.     {scrollTop: $(selector).offset().top},
4.     500
5.   );
6. }
7. //Then to scroll to the class/area you wish to get to like this:
8. $('.area_name').autoscroll();

20. 检测各种浏览器

1. Detect Safari (if( $.browser.safari)),
2. Detect IE6 and over (if ($.browser.msie && $.browser.version > 6 )),
3. Detect IE6 and below (if ($.browser.msie && $.browser.version <= 6 )),
4. Detect FireFox 2 and above (if ($.browser.mozilla && $.browser.version >= '1.8' ))

21. 替换字符串中的单词

1. var el = $('#id');
2. el.html(el.html().replace(/word/ig, ''));

22. 关闭右键的菜单

1. $(document).bind('contextmenu',function(e){ return false; });

23. 定义一个定制的选择器

1. $.expr[':'].mycustomselector = function(element, index, meta, stack){
2. // element- is a DOM element
3. // index - the current loop index in stack
4. // meta - meta data about your selector
5. // stack - stack of all elements to loop
6. // Return true to include current element
7. // Return false to explude current element
8. };
9. // Custom Selector usage:
10. $('.someClasses:test').doSomething();

24. 判断一个元素是否存在

1. if ($('#someDiv').length) {//hooray!!! it exists...}

25. 使用jQuery判断鼠标的左右键点击

1. $("#someelement").live('click', function(e) {
2.     if( (!$.browser.msie && e.button == 0) || ($.browser.msie && e.button == 1) ) {
3.         alert("Left Mouse Button Clicked");
4.     }
5.     else if(e.button == 2)
6.         alert("Right Mouse Button Clicked");
7. });

 

26. 显示或者删除输入框的缺省值

1. //This snippet will show you how to keep a default value
2. //in a text input field for when a user hasn't entered in
3. //a value to replace it
4. swap_val = [];
5. $(".swap").each(function(i){
6.     swap_val[i] = $(this).val();
7.     $(this).focusin(function(){
8.         if ($(this).val() == swap_val[i]) {
9.             $(this).val("");
10.         }
11.     }).focusout(function(){
12.         if ($.trim($(this).val()) == "") {
13.             $(this).val(swap_val[i]);
14.         }
15.     });
16. });
 
1. <INPUT class=swap value="Enter Username here.." type=text>

27. 指定时间后自动隐藏或者关闭元素(1.4支持）

1. //Here's how we used to do it in 1.3.2 using setTimeout
2. setTimeout(function() {
3.   $('.mydiv').hide('blind', {}, 500)
4. }, 5000);
5. //And here's how you can do it with 1.4 using the delay() feature (this is a lot like sleep)
6. $(".mydiv").delay(5000).hide('blind', {}, 500);

28. 动态创建元素到DOM

1. var newgbin1Div = $('');
2. newgbin1Div.attr('id','gbin1.com').appendTo('body');

29. 限制textarea的字符数量

1. jQuery.fn.maxLength = function(max){
2.   this.each(function(){
3.     var type = this.tagName.toLowerCase();
4.     var inputType = this.type? this.type.toLowerCase() : null;
5.     if(type == "input" && inputType == "text" || inputType == "password"){
6.       //Apply the standard maxLength
7.       this.maxLength = max;
8.     }
9.     else if(type == "textarea"){
10.       this.onkeypress = function(e){
11.         var ob = e || event;
12.         var keyCode = ob.keyCode;
13.         var hasSelection = document.selection? document.selection.createRange().text.length > 0 : this.selectionStart != this.selectionEnd;
14.         return !(this.value.length >= max && (keyCode > 50 || keyCode == 32 || keyCode == 0 || keyCode == 13) && !ob.ctrlKey && !ob.altKey && !hasSelection);
15.       };
16.       this.onkeyup = function(){
17.         if(this.value.length > max){
18.           this.value = this.value.substring(0,max);
19.         }
20.       };
21.     }
22.   });
23. };
24. //Usage:
25. $('#gbin1textarea').maxLength(500);

30. 为函数创建一个基本测试用例

1. //Separate tests into modules.
2. module("Module B");
3. test("some other gbin1.com test", function() {
4.   //Specify how many assertions are expected to run within a test.
5.   expect(2);
6.   //A comparison assertion, equivalent to JUnit's assertEquals.
7.   equals( true, false, "failing test" );
8.   equals( true, true, "passing test" );
9. });

31. 使用jQuery克隆元素

1. var cloned = $('#gbin1div').clone();

32. 测试一个元素在jQuery中是否可见

1. if($(element).is(':visible') == 'true') { //The element is Visible }

33. 元素屏幕居中

1. jQuery.fn.center = function () {
2.   this.css('position','absolute');
3.   this.css('top', ( $(window).height() - this.height() ) / +$(window).scrollTop() + 'px');
4.   this.css('left', ( $(window).width() - this.width() ) / 2+$(window).scrollLeft() + 'px');return this;
5. }
6. //Use the above function as: $('#gbin1div').center();

34. 使用特定名字的元素对应的值生成一个数组

1. var arrInputValues = new Array();
2. $("input[name='table[]']").each(function(){
3.      arrInputValues.push($(this).val());
4. });

35. 剔除元素中的HTML

1. (function($) {
2.     $.fn.stripHtml = function() {
3.         var regexp = /<("[^"]*"|'[^']*'|[^'">])*>/gi;
4.         this.each(function() {
5.             $(this).html(
6.                 $(this).html().replace(regexp,"")
7.             );
8.         });
9.         return $(this);
10.     }
11. })(jQuery);
12. //usage:
13. $('p').stripHtml();

36. 使用closest来得到父元素

1. $('#searchBox').closest('div');

37. 使用firebug来记录jQuery事件

1. // Allows chainable logging
2. // Usage: $('#someDiv').hide().log('div hidden').addClass('someClass');
3. jQuery.log = jQuery.fn.log = function (msg) {
4.       if (console){
5.          console.log("%s: %o", msg, this);
6.       }
7.       return this;
8. };

38. 点击链接强制弹出新窗口

1. jQuery('a.popup').live('click', function(){
2.   newwindow=window.open($(this).attr('href'),'','height=200,width=150');
3.   if (window.focus) {newwindow.focus()}
4.   return false;
5. });

39. 点击链接强制打开新标签页

1. jQuery('a.newTab').live('click', function(){
2.   newwindow=window.open($(this).href);
3.   jQuery(this).target = "_blank";
4.   return false;
5. });

40. 使用siblings()来处理同类元素

1. // Rather than doing this
2. $('#nav li').click(function(){
3.     $('#nav li').removeClass('active');
4.     $(this).addClass('active');
5. });
6. // Do this instead
7. $('#nav li').click(function(){
8.     $(this).addClass('active')
9.         .siblings().removeClass('active');
10. });

41. 选择或者不选页面上全部复选框

1. var tog = false; // or true if they are checked on load
2. $('a').click(function() {
3.     $("input[type=checkbox]").attr("checked",!tog);
4.     tog = !tog;
5. });

42. 基于输入文字过滤页面元素

1. //If the value of the element matches that of the entered text
2. //it will be returned
3. $('.gbin1Class').filter(function() {
4.     return $(this).attr('value') == $('input#gbin1Id').val() ;
5.  })

43. 取得鼠标的X和Y坐标

1. $(document).mousemove(function(e){
2. $(document).ready(function() {
3. $().mousemove(function(e){
4. $('#XY').html("Gbin1 X Axis : " + e.pageX + " | Gbin1 Y Axis " + e.pageY);
5. });
6. });

44. 使得整个列表元素(LI)可点击

1. $("ul li").click(function(){
2.   window.location=$(this).find("a").attr("href"); return false;
3. });
 
1. <UL>
2. <LI><A href="#">GBin1 Link 1</A></LI>
3. <LI><A href="#">GBin1 Link 2</A></LI>
4. <LI><A href="#">GBin1 Link 3</A></LI>
5. <LI><A href="#">GBin1 Link 4</A></LI>
6. </UL>

45. 使用jQuery来解析XML

1. function parseXml(xml) {
2.   //find every Tutorial and print the author
3.   $(xml).find("Tutorial").each(function()
4.   {
5.   $("#output").append($(this).attr("author") + "");
6.   });
7. }

46. 判断一个图片是否加载完全

1. $('#theGBin1Image').attr('src', 'image.jpg').load(function() {
2. alert('This Image Has Been Loaded');
3. });

47. 使用jQuery命名事件

1. //Events can be namespaced like this
2. $('input').bind('blur.validation', function(e){
3.     // ...
4. });
5. //The data method also accept namespaces
6. $('input').data('validation.isValid', true);

48. 判断cookie是否激活或者关闭

1. var dt = new Date();
2. dt.setSeconds(dt.getSeconds() + 60);
3. document.cookie = "cookietest=1; expires=" + dt.toGMTString();
4. var cookiesEnabled = document.cookie.indexOf("cookietest=") != -1;
5. if(!cookiesEnabled)
6. {
7.   //cookies have not been enabled
8. }

49.  强制过期cookie

1. var date = new Date();
2. date.setTime(date.getTime() + (x * 60 * 1000));
3. $.cookie('example', 'foo', { expires: date });

50. 使用一个可点击的链接替换页面中所有URL

1. $.fn.replaceUrl = function() {
2.         var regexp = /((ftp|http|https)://(w+:{0,1}w*@)?(S+)(:[0-9]+)?(/|/([w#!:.?+=&%@!-/]))?)/gi;
3.         this.each(function() {
4.             $(this).html(
5.                 $(this).html().replace(regexp,'<A href="$1">$1</A>')
6.             );
7.         });
8.         return $(this);
9.     }
10. //usage
11. $('#GBin1div').replaceUrl();

51: 在表单中禁用“回车键”

大家可能在表单的操作中需要防止用户意外的提交表单，那么下面这段代码肯定非常有帮助：

1. $("#form").keypress(function(e) {
2.   if (e.which == 13) {
3.     return false;
4.   }
5. });

52: 清除所有的表单数据

可能针对不同的表单形式，你需要调用不同类型的清楚方法，不过使用下面这个现成方法，绝对能让你省不少功夫。

1. function clearForm(form) {
2.   // iterate over all of the inputs for the form
3.   // element that was passed in
4.   $(':input', form).each(function() {
5.     var type = this.type;
6.     var tag = this.tagName.toLowerCase(); // normalize case
7.     // it's ok to reset the value attr of text inputs,
8.     // password inputs, and textareas
9.     if (type == 'text' || type == 'password' || tag == 'textarea')
10.       this.value = "";
11.     // checkboxes and radios need to have their checked state cleared
12.     // but should *not* have their 'value' changed
13.     else if (type == 'checkbox' || type == 'radio')
14.       this.checked = false;
15.     // select elements need to have their 'selectedIndex' property set to -1
16.     // (this works for both single and multiple select elements)
17.     else if (tag == 'select')
18.       this.selectedIndex = -1;
19.   });
20. };

53: 将表单中的按钮禁用

下面的代码对于ajax操作非常有用，你可以有效的避免用户多次提交数据，个人也经常使用：

禁用按钮：
 
1. $("#somebutton").attr("disabled", true);
 
 启动按钮：
 
1. $("#submit-button").removeAttr("disabled");

可能大家往往会使用.attr(‘disabled’,false);，不过这是不正确的调用。

54: 输入内容后启用递交按钮

这个代码和上面类似，都属于帮助用户控制表单递交按钮。使用这段代码后，递交按钮只有在用户输入指定内容后才可以启动。

1. $('#username').keyup(function() {
2.     $('#submit').attr('disabled', !$('#username').val()); 
3. });

55: 禁止多次递交表单

多次递交表单对于web应用来说是个比较头疼的问题，下面的代码能够很好的帮助你解决这个问题：

1. $(document).ready(function() {
2.   $('form').submit(function() {
3.     if(typeof jQuery.data(this, "disabledOnSubmit") == 'undefined') {
4.       jQuery.data(this, "disabledOnSubmit", { submited: true });
5.       $('input[type=submit], input[type=button]', this).each(function() {
6.         $(this).attr("disabled", "disabled");
7.       });
8.       return true;
9.     }
10.     else
11.     {
12.       return false;
13.     }
14.   });
15. });

56: 高亮显示目前聚焦的输入框标示

有时候你需要提示用户目前操作的输入框，你可以使用下面代码高亮显示标示：

1. $("form :input").focus(function() {
2.   $("label[for='" + this.id + "']").addClass("labelfocus");
3. }).blur(function() {
4.   $("label").removeClass("labelfocus");
5. });

57: 动态方式添加表单元素

这个方法可以帮助你动态的添加表单中的元素，比如，input等：

1. //change event on password1 field to prompt new input
2. $('#password1').change(function() {
3.         //dynamically create new input and insert after password1
4.         $("#password1").append("<input type='text' name='password2' id='password2' />");
5. });

58: 自动将数据导入selectbox中

下面代码能够使用ajax数据自动生成选择框的内容

1. $(function(){
2.   $("select#ctlJob").change(function(){
3.     $.getJSON("/select.php",{id: $(this).val(), ajax: 'true'}, function(j){
4.       var options = '';
5.       for (var i = 0; i < j.length; i++) {
6.         options += '<option value="' + j[i].optionValue + '">' + j[i].optionDisplay + '</option>';
7.       }
8.       $("select#ctlPerson").html(options);
9.     })
10.   })
11. })

59: 判断一个复选框是否被选中

代码很简单，如下：

1. $('#checkBox').attr('checked');

60: 使用代码来递交表单

代码很简单，如下：

1. $("#myform").submit();

希望大家觉得这些jQuery代码会对你的开发有帮助，如果你也有类似的jQuery代码或者jQuery插件，欢迎一起分享！