下面小编就为大家带来一篇jQuery 常用代码集锦(必看篇)。小编觉得挺不错的，现在分享给大家，也给大家做个参考

1. 选择或者不选页面上全部复选框

var tog = false; // or true if they are checked on load

$('a').click(function() {

 $("input[type=checkbox]").attr("checked",!tog);

 tog = !tog;

});

2. 取得鼠标的X和Y坐标

$(document).mousemove(function(e){

$(document).ready(function() {

$().mousemove(function(e){

$('#XY').html("Gbin1 X Axis : " + e.pageX + " | Gbin1 Y Axis " + e.pageY);

});

});

3. 判断一个图片是否加载完全

$('#theGBin1Image').attr('src', 'image.jpg').load(function() {

alert('This Image Has Been Loaded');

});

4. 判断cookie是否激活或者关闭

var dt = new Date();

dt.setSeconds(dt.getSeconds() + 60);

document.cookie = "cookietest=1; expires=" + dt.toGMTString();

var cookiesEnabled = document.cookie.indexOf("cookietest=") != -1;

if(!cookiesEnabled)

{

 //cookies have not been enabled

}

5. 强制过期cookie

var date = new Date();

date.setTime(date.getTime() + (x * 60 * 1000));

$.cookie('example', 'foo', { expires: date });

6. 在表单中禁用“回车键”，表单的操作中需要防止用户意外的提交表单

$("#form").keypress(function(e) {

 if (e.which == 13) {

 return false;

 }

});

7. 清除所有的表单数据

function clearForm(form) {

 // iterate over all of the inputs for the form

 // element that was passed in

 $(':input', form).each(function() {

 var type = this.type;

 var tag = this.tagName.toLowerCase(); // normalize case

 // it's ok to reset the value attr of text inputs,

 // password inputs, and textareas

 if (type == 'text' || type == 'password' || tag == 'textarea')

  this.value = "";

 // checkboxes and radios need to have their checked state cleared

 // but should *not* have their 'value' changed

 else if (type == 'checkbox' || type == 'radio')

  this.checked = false;

 // select elements need to have their 'selectedIndex' property set to -1

 // (this works for both single and multiple select elements)

 else if (tag == 'select')

  this.selectedIndex = -1;

 });

};

8.禁止多次递交表单

$(document).ready(function() {

 $('form').submit(function() {

 if(typeof jQuery.data(this, "disabledOnSubmit") == 'undefined') {

  jQuery.data(this, "disabledOnSubmit", { submited: true });

  $('input[type=submit], input[type=button]', this).each(function() {

  $(this).attr("disabled", "disabled");

  });

  return true;

 }

 else

 {

  return false;

 }

 });

});

9. 自动将数据导入selectbox中

$(function(){

 $("select#ctlJob").change(function(){

 $.getJSON("/select.php",{id: $(this).val(), ajax: 'true'}, function(j){

  var options = '';

  for (var i = 0; i < j.length; i++) {

  options += '<option value="' + j[i].optionValue + '">' + j[i].optionDisplay + '</option>';

  }

  $("select#ctlPerson").html(options);

 })

 })

})

10. 创建一个嵌套的过滤器

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

11. 使用has()来判断一个元素是否包含特定的class或者元素

//jQuery 1.4.* includes support for the has method. This method will find 

//if a an element contains a certain other element class or whatever it is 

//you are looking for and do anything you want to them. 

$("input").has(".email").addClass("email_icon");

12. 使用jQuery切换样式

//Look for the media-type you wish to switch then set the href to your new style sheet 

$('link[media='screen']').attr('href', 'Alternative.css');

13. 如何正确使用ToggleClass

//Toggle class allows you to add or remove a class 

//from an element depending on the presence of that 

//class. Where some developers would use: 

a.hasClass('blueButton') ? a.removeClass('blueButton') : a.addClass('blueButton'); 

//toggleClass allows you to easily do this using 

a.toggleClass('blueButton');

14. 使用jQuery来替换一个元素

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

15.绑定一个函数到一个事件

$('#foo').bind('click', function() { 

 alert('User clicked on "foo."'); 

});

16. 使用jQuery预加载图片

jQuery.preloadImages = function() { for(var i = 0; i').attr('src', arguments[i]); } }; 

// Usage $.preloadImages('image1.gif', '/path/to/image2.png', 'some/image3.jpg');

17. 设置任何匹配一个选择器的事件处理程序

$('button.someClass').live('click', someFunction);

 //Note that in jQuery 1.4.2, the delegate and undelegate options have been

 //introduced to replace live as they offer better support for context

 //For example, in terms of a table where before you would use..

 // .live()

 $("table").each(function(){

 $("td", this).live("hover", function(){

 $(this).toggleClass("hover");

 });

 });

 //Now use..

 $("table").delegate("td", "hover", function(){

 $(this).toggleClass("hover");

});

18. 自动的滚动到页面特定区域

jQuery.fn.autoscroll = function(selector) {

 $('html,body').animate(

 {scrollTop: $(selector).offset().top},

 );

}

//Then to scroll to the class/area you wish to get to like this:

$('.area_name').autoscroll();

19.检测各种浏览器

Detect Safari (if( $.browser.safari)),

Detect IE6 and over (if ($.browser.msie && $.browser.version > 6 )),

Detect IE6 and below (if ($.browser.msie && $.browser.version <= 6 )),

Detect FireFox 2 and above (if ($.browser.mozilla && $.browser.version >= '1.8' )

20.限制textarea的字符数量

jQuery.fn.maxLength = function(max){

 this.each(function(){

 var type = this.tagName.toLowerCase();

 var inputType = this.type? this.type.toLowerCase() : null;

 if(type == "input" && inputType == "text" || inputType == "password"){

  //Apply the standard maxLength

  this.maxLength = max;

 }

 else if(type == "textarea"){

  this.onkeypress = function(e){

  var ob = e || event;

  var keyCode = ob.keyCode;

  var hasSelection = document.selection? document.selection.createRange().text.length > 0 : this.selectionStart != this.selectionEnd;

  return !(this.value.length >= max && (keyCode > 50 || keyCode == 32 || keyCode == 0 || keyCode == 13) && !ob.ctrlKey && !ob.altKey && !hasSelection);

  };

  this.onkeyup = function(){

  if(this.value.length > max){

   this.value = this.value.substring(0,max);

  }

  };

 }

 });

};

//Usage:

$('#gbin1textarea').maxLength(500);

21.使用jQuery克隆元素

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

22. 元素屏幕居中

jQuery.fn.center = function () {

 this.css('position','absolute');

 this.css('top', ( $(window).height() - this.height() ) / +$(window).scrollTop() + 'px');

 this.css('left', ( $(window).width() - this.width() ) / 2+$(window).scrollLeft() + 'px');return this;

}

//Use the above function as: $('#gbin1div').center();

23 .简单的tab标签切换

jQuery('#meeting_tabs ul li').click(function(){

  jQuery(this).addClass('tabulous_active').siblings().removeClass('tabulous_active');

  jQuery('#tabs_container>.pane:eq('+jQuery(this).index()+')').show().siblings().hide(); 

 })

<div id="meeting_tabs">

    <ul>

      <li class="tabulous_active"><a href="#" title="">进行中</a></li>

      <li><a href="#" title="">未开始</a></li>

      <li><a href="#" title="">已结束</a></li>

      <li><a href="#" title="">全部</a></li>

     </ul>

 <div id="tabs_container">

   <div class="pane"  >1</div>

   <div class="pane"  >2</div>

   <div class="pane"  >3</div>

   <div class="pane"  >4</div>

 </div>

</div>

以上这篇jQuery 常用代码集锦(必看篇)就是小编分享给大家的全部内容了，希望能给大家一个参考