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| 关键词： 代码 function 元素 nbsp jQuery 一个 element class browser var |
本文实例总结了30个经典的jQuery代码开发技巧。分享给大家供大家参考。具体如下：1. 创建一个嵌套的过滤器复制代码代码如下:.filter(":not(:has(.selected))") //去掉所有不包含class为.selected的元素2. 重用你的元素查询复制代码代码如下: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>3. 使用has()来判断一个元素是否包含特定的class或者元素复制代码代码如下://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. $("input").has(".email").addClass("email_icon");4. 使用jQuery切换样式复制代码代码如下://Look for the media-type you wish to switch then set the href to your new style sheet$('link[media='screen']').attr('href', 'Alternative.css');5. 限制选择的区域复制代码代码如下://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 timesvar in_stock = $('#shopping_cart_items input.is_in_stock');<ul id="shopping_cart_items"><li> <input value="Item-X" name="item" type="radio"> Item X</li><li> <input value="Item-Y" name="item" type="radio"> Item Y</li><li> <input value="Item-Z" name="item" type="radio"> Item Z</li></ul>6. 如何正确使用ToggleClass复制代码代码如下://Toggle class allows you to add or remove a class//from an element depending on the presence of that//class. Where some developers would use:a.hasClass('blueButton') ? a.removeClass('blueButton') : a.addClass('blueButton');//toggleClass allows you to easily do this usinga.toggleClass('blueButton');7. 设置IE指定的功能复制代码代码如下:if ($.browser.msie) { // Internet Explorer is a sadist.}8. 使用jQuery来替换一个元素复制代码代码如下:$('#thatdiv').replaceWith('fnuh');9. 验证一个元素是否为空复制代码代码如下:if ($('#keks').html()) {//Nothing found ;}10. 在无序的set中查找一个元素的索引复制代码代码如下:$("ul > li").click(function () { var index = $(this).prevAll().length; });11. 绑定一个函数到一个事件复制代码代码如下:$('#foo').bind('click', function() { alert('User clicked on "foo."'); });12. 添加HTML到一个元素复制代码代码如下:$('#lal').append('sometext');13. 创建元素时使用对象来定义属性复制代码代码如下:var e = $("", { href: "#", class: "a-class another-class", title: "..." });14. 使用过滤器过滤多属性复制代码代码如下://This precision-based approached can be useful when you use//lots of similar input elements which have different typesvar elements = $('#someid input[type=sometype][value=somevalue]').get();15. 使用jQuery预加载图片复制代码代码如下:jQuery.preloadImages = function() { for(var i = 0; i').attr('src', arguments[i]); } }; // Usage $.preloadImages('image1.webp', '/path/to/image2.webp', 'some/image3.webp');16. 设置任何匹配一个选择器的事件处理程序[code]$('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(){ $(this).toggleClass("hover"); });17. 找到被选择到的选项(option)元素复制代码代码如下:$('#someElement').find('option:selected');18. 隐藏包含特定值的元素复制代码代码如下:$("p.value:contains('thetextvalue')").hide();19. 自动的滚动到页面特定区域复制代码代码如下: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();20. 检测各种浏览器复制代码代码如下: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' ))21. 替换字符串中的单词复制代码代码如下:var el = $('#id'); el.html(el.html().replace(/word/ig, ''));22. 关闭右键的菜单复制代码代码如下:$(document).bind('contextmenu',function(e){ return false; });23. 定义一个定制的选择器复制代码代码如下:$.expr[':'].mycustomselector = function(element, index, meta, stack){// element- is a DOM element// index - the current loop index in stack// meta - meta data about your selector// stack - stack of all elements to loop// Return true to include current element// Return false to explude current element};// Custom Selector usage:$('.someClasses:test').doSomething();24. 判断一个元素是否存在复制代码代码如下:if ($('#someDiv').length) {//hooray!!! it exists...}25. 使用jQuery判断鼠标的左右键点击复制代码代码如下:$("#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"); });26. 显示或者删除输入框的缺省值复制代码代码如下://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 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）复制代码代码如下://Here's how we used to do it in 1.3.2 using setTimeout setTimeout(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);28. 动态创建元素到DOM复制代码代码如下:var newgbin1Div = $('');newgbin1Div.attr('id','gbin1.com').appendTo('body');29. 限制textarea的字符数量复制代码代码如下: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);30. 为函数创建一个基本测试用例复制代码代码如下://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" ); });希望本文所述对大家的jquery程序设计有所帮助。 |
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