由于內容比較多建議用CTRL+F搜索
偶然在網上看到這些不錯的jQuery代碼開發技巧。原文收集了30個，另外查找的時候發現了還有20個。加上另外十個實用的jQuery代碼片段，共60個代碼技巧，收集在一起分享給大家。
.filter(":not(:has(.selected))") //去掉所有不包含class為.selected的元素var allItems = $("div.item"); var keepList = $("div#container1 div.item"); <div>class names: $(formToLookAt + " input:checked").each(function() { keepListkeepList = keepList.filter("." + $(this).attr("name")); });</div>//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");//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'); //Where possible, pre-fix your class names with a tag name //so that jQuery doesn't have to spend more time searching //for the element you're after. Also remember that anything //you can do to be more specific about where the element is //on your page will cut down on execution/search times var in_stock = $('#shopping_cart_items input.is_in_stock');<ul id="shopping_cart_items"> <li> <input value="Item-X" name="item" class="is_in_stock" type="radio"> Item X</li> <li> <input value="Item-Y" name="item" class="3-5_days" type="radio"> Item Y</li> <li> <input value="Item-Z" name="item" class="unknown" type="radio"> Item Z</li> </ul>
//Toggle class allows you to add or remove a class //from an element depending on the presence of that //class. Where some developers would use: a.hasClass('blueButton') ? a.removeClass('blueButton') : a.addClass('blueButton'); //toggleClass allows you to easily do this using a.toggleClass('blueButton'); if ($.browser.msie) { // Internet Explorer is a sadist. } $('#thatdiv').replaceWith('fnuh');if ($('#keks').html()) { //Nothing found ;} $("ul > li").click(function () { var index = $(this).prevAll().length; });$('#foo').bind('click', function() { alert('User clicked on "foo."'); }); $('#lal').append('sometext');var e = $("", { href: "#", class: "a-class another-class", title: "..." });//This precision-based approached can be useful when you use //lots of similar input elements which have different types var elements = $('#someid input[type=sometype][value=somevalue]').get(); jQuery.preloadImages = function() { for(var i = 0; i').attr('src', arguments[i]); } }; // Usage $.preloadImages('image1.gif', '/path/to/image2.png', 'some/image3.jpg'); $('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(){ $(this).toggleClass("hover");});$('#someElement').find('option:selected');$("p.value:contains('thetextvalue')").hide();jQuery.fn.autoscroll = function(selector) { $('html,body').animate( {scrollTop: $(selector).offset().top}, 500 );}//Then to scroll to the class/area you wish to get to like this:$('.area_name').autoscroll();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' ))
var el = $('#id');el.html(el.html().replace(/word/ig, ''));$(document).bind('contextmenu',function(e){ return false; });$.expr[':'].mycustomselector = function(element, index, meta, stack){// element- is a DOM element// index - the current loop index in stack// meta - meta data about your selector// stack - stack of all elements to loop// Return true to include current element// Return false to explude current element};// Custom Selector usage:$('.someClasses:test').doSomething();if ($('#someDiv').length) {//hooray!!! it exists...}$("#someelement").live('click', function(e) { if( (!$.browser.msie && e.button == 0) || ($.browser.msie && e.button == 1) ) { alert("Left Mouse Button Clicked"); } else if(e.button == 2) alert("Right Mouse Button Clicked");});//This snippet will show you how to keep a default value//in a text input field for when a user hasn't entered in//a value to replace itswap_val = [];$(".swap").each(function(i){ swap_val[i] = $(this).val(); $(this).focusin(function(){ if ($(this).val() == swap_val[i]) { $(this).val(""); } }).focusout(function(){ if ($.trim($(this).val()) == "") { $(this).val(swap_val[i]); } });});<INPUT class=swap value="Enter Username here.." type=text>
//Here's how we used to do it in 1.3.2 using setTimeoutsetTimeout(function() { $('.mydiv').hide('blind', {}, 500)}, 5000);//And here's how you can do it with 1.4 using the delay() feature (this is a lot like sleep)$(".mydiv").delay(5000).hide('blind', {}, 500);var newgbin1Div = $('');newgbin1Div.attr('id','gbin1.com').appendTo('body');jQuery.fn.maxLength = function(max){ this.each(function(){ var type = this.tagName.toLowerCase(); var inputType = this.type? this.type.toLowerCase() : null; if(type == "input" && inputType == "text" || inputType == "password"){ //Apply the standard maxLength this.maxLength = max; } else if(type == "textarea"){ this.onkeypress = function(e){ var ob = e || event; var keyCode = ob.keyCode; var hasSelection = document.selection? document.selection.createRange().text.length > 0 : this.selectionStart != this.selectionEnd; return !(this.value.length >= max && (keyCode > 50 || keyCode == 32 || keyCode == 0 || keyCode == 13) && !ob.ctrlKey && !ob.altKey && !hasSelection); }; this.onkeyup = function(){ if(this.value.length > max){ this.value = this.value.substring(0,max); } }; } });};//Usage:$('#gbin1textarea').maxLength(500);//Separate tests into modules.module("Module B");test("some other gbin1.com test", function() { //Specify how many assertions are expected to run within a test. expect(2); //A comparison assertion, equivalent to JUnit's assertEquals. equals( true, false, "failing test" ); equals( true, true, "passing test" );});var cloned = $('#gbin1div').clone();if($(element).is(':visible') == 'true') { //The element is Visible }33. 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: $('#gbin1div').center();var arrInputValues = new Array();$("input[name='table[]']").each(function(){ arrInputValues.push($(this).val());});(function($) { $.fn.stripHtml = function() { var regexp = /<("[^"]*"|'[^']*'|[^'">])*>/gi; this.each(function() { $(this).html( $(this).html().replace(regexp,"") ); }); return $(this); }})(jQuery);//usage:$('p').stripHtml();$('#searchBox').closest('div');// Allows chainable logging// Usage: $('#someDiv').hide().log('div hidden').addClass('someClass');jQuery.log = jQuery.fn.log = function (msg) { if (console){ console.log("%s: %o", msg, this); } return this;};jQuery('a.popup').live('click', function(){ newwindow=window.open($(this).attr('href'),'','height=200,width=150'); if (window.focus) {newwindow.focus()} return false;});jQuery('a.newTab').live('click', function(){ newwindow=window.open($(this).href); jQuery(this).target = "_blank"; return false;});// Rather than doing this$('#nav li').click(function(){ $('#nav li').removeClass('active'); $(this).addClass('active');});// Do this instead$('#nav li').click(function(){ $(this).addClass('active') .siblings().removeClass('active');});var tog = false; // or true if they are checked on load$('a').click(function() { $("input[type=checkbox]").attr("checked",!tog); tog = !tog;});//If the value of the element matches that of the entered text//it will be returned$('.gbin1Class').filter(function() { return $(this).attr('value') == $('input#gbin1Id').val() ; })$(document).mousemove(function(e){$(document).ready(function() {$().mousemove(function(e){$('#XY').html("Gbin1 X Axis : " + e.pageX + " | Gbin1 Y Axis " + e.pageY);});});$("ul li").click(function(){ window.location=$(this).find("a").attr("href"); return false;});<UL><LI><A href="#">GBin1 Link 1</A></LI><LI><A href="#">GBin1 Link 2</A></LI><LI><A href="#">GBin1 Link 3</A></LI><LI><A href="#">GBin1 Link 4</A></LI></UL>
function parseXml(xml) { //find every Tutorial and print the author $(xml).find("Tutorial").each(function() { $("#output").append($(this).attr("author") + ""); });}$('#theGBin1Image').attr('src', 'image.jpg').load(function() {alert('This Image Has Been Loaded');});//Events can be namespaced like this$('input').bind('blur.validation', function(e){ // ...});//The data method also accept namespaces$('input').data('validation.isValid', true);var dt = new Date();dt.setSeconds(dt.getSeconds() + 60);document.cookie = "cookietest=1; expires=" + dt.toGMTString();var cookiesEnabled = document.cookie.indexOf("cookietest=") != -1;if(!cookiesEnabled){ //cookies have not been enabled}var date = new Date();date.setTime(date.getTime() + (x * 60 * 1000));$.cookie('example', 'foo', { expires: date });$.fn.replaceUrl = function() { var regexp = /((ftp|http|https)://(w+:{0,1}w*@)?(S+)(:[0-9]+)?(/|/([w#!:.?+=&%@!-/]))?)/gi; this.each(function() { $(this).html( $(this).html().replace(regexp,'<A href="$1">$1</A>') ); }); return $(this); }//usage$('#GBin1div').replaceUrl(); 大家可能在表單的操作中需要防止用戶意外的提交表單，那么下面這段代碼肯定非常有幫助：
$("#form").keypress(function(e) { if (e.which == 13) { return false; }});可能針對不同的表單形式，你需要調用不同類型的清楚方法，不過使用下面這個現成方法，絕對能讓你省不少功夫。
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; });};下面的代碼對于ajax操作非常有用，你可以有效的避免用戶多次提交數據，個人也經常使用：
禁用按鈕：
$("#somebutton").attr("disabled", true);啟動按鈕：
$("#submit-button").removeAttr("disabled");可能大家往往會使用.attr(‘disabled',false);，不過這是不正確的調用。
這個代碼和上面類似，都屬于幫助用戶控制表單遞交按鈕。使用這段代碼后，遞交按鈕只有在用戶輸入指定內容后才可以啟動。
$('#username').keyup(function() { $('#submit').attr('disabled', !$('#username').val()); });多次遞交表單對于web應用來說是個比較頭疼的問題，下面的代碼能夠很好的幫助你解決這個問題：
$(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; } });});有時候你需要提示用戶目前操作的輸入框，你可以使用下面代碼高亮顯示標示：
$("form :input").focus(function() { $("label[for='" + this.id + "']").addClass("labelfocus");}).blur(function() { $("label").removeClass("labelfocus");});這個方法可以幫助你動態的添加表單中的元素，比如，input等：
//change event on password1 field to prompt new input$('#password1').change(function() { //dynamically create new input and insert after password1 $("#password1").append("<input type='text' name='password2' id='password2' />");});下面代碼能夠使用ajax數據自動生成選擇框的內容
$(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); }) })})代碼很簡單，如下：
$('#checkBox').attr('checked');代碼很簡單，如下：
$("#myform").submit();
新聞熱點
疑難解答
