jQuery实用技巧必备（上）

2019-11-20 11:21:15

字体：大中小

来源：转载

供稿：网友

本文实例总结了经典且实用的jQuery代码开发技巧。分享给大家供大家参考。具体如下：

1. 禁止右键点击

$(document).ready(function(){ $(document).bind("contextmenu",function(e){ return false; });});

2. 隐藏搜索文本框文字
Hide when clicked in the search field, the value.(example can be found below in the comment fields)

$(document).ready(function() {$("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. 在新窗口中打开链接
XHTML 1.0 Strict doesn't allow this attribute in the code, so use this to keep the code valid.

$(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.jb51.com" rel=external>open link</a>

4. 检测浏览器
注: 在版本jQuery 1.4中，$.support 替换掉了$.browser 变量

$(document).ready(function() {// Target Firefox 2 and aboveif ($.browser.mozilla && $.browser.version >= "1.8" ){ // do something}// Target Safariif( $.browser.safari ){ // do something}// Target Chromeif( $.browser.chrome){ // do something}// Target Caminoif( $.browser.camino){ // do something}// Target Operaif( $.browser.opera){ // do something}// Target IE6 and belowif ($.browser.msie && $.browser.version <= 6 ){ // do something}// Target anything above IE6if ($.browser.msie && $.browser.version > 6){ // do something}});

5. 预加载图片
This piece of code will prevent the loading of all images, which can be useful if you have a site with lots of images.

$(document).ready(function() {jQuery.preloadImages = function(){ for(var i = 0; i<ARGUMENTS.LENGTH; jQuery(?<img { i++)>").attr("src", arguments[i]); }}// how to use$.preloadImages("image1.jpg");});

6. 页面样式切换

$(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 type=text/css href="default.css">// the links<A class=Styleswitcher href="#" rel=default.css>Default Theme</A><A class=Styleswitcher href="#" rel=red.css>Red Theme</A><A class=Styleswitcher href="#" rel=blue.css>Blue Theme</A>});

7. 列高度相同
如果使用了两个CSS列，使用此种方式可以是两列的高度相同。

$(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. 动态控制页面字体大小
用户可以改变页面字体大小

$(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); return false; }); // 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); return false; });});

9. 返回页面顶部功能
For a smooth(animated) ride back to the top(or any location).

$(document).ready(function() {$('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); return false; } } });// 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. 获得鼠标指针ＸＹ值
Want to know where your mouse cursor is?

$(document).ready(function() { $().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); });// how to use<DIV id=XY></DIV>});

11.返回顶部按钮
你可以利用 animate 和 scrollTop 来实现返回顶部的动画，而不需要使用其他插件。

// Back to top$('a.top').click(function () { $(document.body).animate({scrollTop: 0}, 800); return false;});<!-- Create an anchor tag --><a class="top" href="#">Back to top</a>

改变scrollTop 的值可以调整返回距离顶部的距离，而 animate 的第二个参数是执行返回动作需要的时间(单位：毫秒)。

今天为大家先介绍一部分jQuery技巧，后续文章会继续更新，希望大家持续关注。

上一篇：jQuery实用技巧必备（中）

下一篇：jQuery zclip插件实现跨浏览器复制功能