jQuery已经成为任何web项目的重要组成部分。它为网站提供了交互性的通过移动HTML元素，创建自定义动画，处理事件，选择DOM元素，检索整个document ，让最终用户有一个更好的体验。

在这篇文章中我已经收集了20 +个可重复使用的jQuery代码片段，你可以很容易地复制并直接粘贴到你的项目中。

图片的延迟加载

jQuery(document).ready(function() {      jQuery("img.lazy").lazy({          delay: 2000      });  });

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预先载入图像

(function($) {    var cache = [];    // Arguments are image paths relative to the current page.    $.preLoadImages = function() {      var args_len = arguments.length;      for (var i = args_len; i--;) {        var cacheImage = document.createElement('img');        cacheImage.src = arguments[i];        cache.push(cacheImage);      }    }  })(jQuery)

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部分页面刷新

setInterval(function() {   $("#refresh").load(location.href+" #refresh>*","");  }, 10000);

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延迟动画/效果

$(".alert").delay(2000).fadeOut();

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Open external link in New Window

$('a').each(function() {     var a = new RegExp('/' + window.location.host + '/');     if(!a.test(this.href)) {         $(this).click(function(event) {             event.preventDefault();             event.stopPropagation();             window.open(this.href, '_blank');         });     }  });

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Make Everything Mobile Friendly

var scr = document.createElement('script');  scr.setAttribute('src', 'https://ajax.googleapis.com/ajax/libs/jquery/1.5.2/  jquery.min.js');  document.body.appendChild(scr);    scr.onload = function(){     $('div').attr('class', '').attr('id', '').css({    'margin' : 0,    'padding' : 0,    'width': '100%',    'clear':'both'   });  };

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Image Resize Using jQuery

$(window).bind("load", function() {   // IMAGE RESIZE   $('#product_cat_list img').each(function() {    var maxWidth = 120;    var maxHeight = 120;    var ratio = 0;    var width = $(this).width();    var height = $(this).height();      if(width > maxWidth){     ratio = maxWidth / width;     $(this).css("width", maxWidth);     $(this).css("height", height * ratio);     height = height * ratio;    }    var width = $(this).width();    var height = $(this).height();    if(height > maxHeight){     ratio = maxHeight / height;     $(this).css("height", maxHeight);     $(this).css("width", width * ratio);     width = width * ratio;    }   });   //$("#contentpage img").show();   // IMAGE RESIZE  });

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Smooth Scrolling

$(function() {    $('a[href*=#]:not([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) {          $('html,body').animate({            scrollTop: target.offset().top          }, 1000);          return false;        }      }    });  });

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Window load event with minimum delay

(function fn() {      fn.now = +new Date;      $(window).load(function() {         if (+new Date - fn.now < 500) setTimeout(fn, 500);       // Do something      });    })();

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jQuery Accordion

(function($) {      var allPanels = $('.accordion > dd').hide();      $('.accordion > dt > a').click(function() {      allPanels.slideUp();      $(this).parent().next().slideDown();      return false;    });    })(jQuery);

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Simple Auto-Playing Slideshow

$("#slideshow > div:gt(0)").hide();    setInterval(function() {     $('#slideshow > div:first')      .fadeOut(1000)      .next()      .fadeIn(1000)      .end()      .appendTo('#slideshow');  },  3000);

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Shuffle DOM Elements

(function($){        $.fn.shuffle = function() {            var allElems = this.get(),              getRandom = function(max) {                  return Math.floor(Math.random() * max);              },              shuffled = $.map(allElems, function(){                  var random = getRandom(allElems.length),                      randEl = $(allElems[random]).clone(true)[0];                  allElems.splice(random, 1);                  return randEl;             });            this.each(function(i){              $(this).replaceWith($(shuffled[i]));          });            return $(shuffled);        };    })(jQuery);

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Scroll Page Horizontally With Mouse Wheel

$(function() {       $("body").mousewheel(function(event, delta) {          this.scrollLeft -= (delta * 30);          event.preventDefault();       });    });

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Load Only a Section of a Page

$("#mainNav").load("/store #mainNav")

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Highlight Related Label when Input in Focus

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

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Highlight All Links To Current Page

$(function(){   $("a").each(function(){      if ($(this).attr("href") == window.location.pathname){     $(this).addClass("selected");      }   });  });

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Better Broken Image Handling

// Replace source  $('img').error(function(){          $(this).attr('src', 'missing.png');  });    // Or, hide them  $("img").error(function(){          $(this).hide();  });

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Load Content on Scroll Automatically

var loading = false;  $(window).scroll(function(){   if((($(window).scrollTop()+$(window).height())+250)>=$(document).  height()){    if(loading == false){     loading = true;     $('#loadingbar').css("display","block");     $.get("load.php?start="+$('#loaded_max').val(),   function(loaded){      $('body').append(loaded);      $('#loaded_max').val(parseInt($('#loaded_max')  .val())+50);      $('#loadingbar').css("display","none");      loading = false;     });    }   }  });    $(document).ready(function() {   $('#loaded_max').val(50);  });

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Prevent Multiple Submit of Your Form

$(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;      }    });  });

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Make Entire Div Clickable

$(".myBox").click(function(){       window.location=$(this).find("a").attr("href");        return false;  });

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Toggle Text

$("#more-less-options-button").click(function() {       var txt = $("#extra-options").is(':visible') ? 'more options' : 'less   options';       $("#more-less-options-button").text(txt);       $("#extra-options").slideToggle();  });

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