(function($){ $.fn.mailAutoComplete = function(options){ var defaults = {  boxClass: "mailListBox", //外部box樣式  listClass: "mailListDefault", //默認的列表樣式  focusClass: "mailListFocus", //列表選樣式中  markCalss: "mailListHlignt", //高亮樣式  zIndex: 1,  autoClass: true, //是否使用插件自帶class樣式  mailArr: ["qq.com","gmail.com","126.com","163.com","hotmail.com","yahoo.com","yahoo.com.cn","live.com","sohu.com","sina.com"], //郵件數組  textHint: false, //文字提示的自動顯示與隱藏  hintText: "",  focusColor: "#333"  //blurColor: "#999" }; var settings = $.extend({}, defaults, options || {});  //頁面裝載CSS樣式 if(settings.autoClass && $("#mailListAppendCss").size() === 0){  $('<style id="mailListAppendCss" type="text/css">.mailListBox{border:1px solid #369; background:#fff; font:12px/20px Arial;}.mailListDefault{padding:0 5px;cursor:pointer;white-space:nowrap;}.mailListFocus{padding:0 5px;cursor:pointer;white-space:nowrap;background:#369;color:white;}.mailListHlignt{color:red;}.mailListFocus .mailListHlignt{color:#fff;}</style>').appendTo($("head"));  } var cb = settings.boxClass, cl = settings.listClass, cf = settings.focusClass, cm = settings.markCalss; //插件的class變量 var z = settings.zIndex, newArr = mailArr = settings.mailArr, hint = settings.textHint, text = settings.hintText, fc = settings.focusColor, bc = settings.blurColor; //創建郵件內部列表內容 $.createHtml = function(str, arr, cur){  var mailHtml = "";  if($.isArray(arr)){  $.each(arr, function(i, n){   if(i === cur){   mailHtml += '<div class="mailHover '+cf+'" id="mailList_'+i+'"><span class="'+cm+'">'+str+'</span>@'+arr[i]+'</div>';    }else{   mailHtml += '<div class="mailHover '+cl+'" id="mailList_'+i+'"><span class="'+cm+'">'+str+'</span>@'+arr[i]+'</div>';    }  });  }  return mailHtml; }; //一些全局變量 var index = -1, s; $(this).each(function(){  var that = $(this), i = $(".justForJs").size();   if(i > 0){ //只綁定一個文本框   return;   }  var w = that.outerWidth(), h = that.outerHeight(); //獲取當前對象（即文本框）的寬高  //樣式的初始化  that.wrap('<span style="display:inline-block;position:relative;"></span>')  .before('<div id="mailListBox_'+i+'" class="justForJs '+cb+'" style="min-width:'+w+'px;_width:'+w+'px;position:absolute;left:-6000px;top:'+h+'px;z-index:'+z+';"></div>');  var x = $("#mailListBox_" + i), liveValue; //列表框對象  that.focus(function(){  //父標簽的層級  $(this).css("color", fc).parent().css("z-index", z);   //提示文字的顯示與隱藏  if(hint && text){   var focus_v = $.trim($(this).val());   if(focus_v === text){   $(this).val("");   }  }  //鍵盤事件  $(this).keyup(function(e){   s = v = $.trim($(this).val());    if(/@/.test(v)){   s = v.replace(/@.*/, "");   }   if(v.length > 0){   //如果按鍵是上下鍵   if(e.keyCode === 38){    //向上    if(index <= 0){    index = newArr.length;     }    index--;   }else if(e.keyCode === 40){    //向下    if(index >= newArr.length - 1){    index = -1;    }    index++;   }else if(e.keyCode === 13){    //回車    if(index > -1 && index < newArr.length){    //如果當前有激活列表    $(this).val($("#mailList_"+index).text());     }   }else{    if(/@/.test(v)){    index = -1;    //獲得@后面的值    //s = v.replace(/@.*/, "");    //創建新匹配數組    var site = v.replace(/.*@/, "");    newArr = $.map(mailArr, function(n){     var reg = new RegExp(site);      if(reg.test(n)){     return n;      }    });    }else{    newArr = mailArr;    }   }   x.html($.createHtml(s, newArr, index)).css("left", 0);   if(e.keyCode === 13){    //回車    if(index > -1 && index < newArr.length){    //如果當前有激活列表    x.css("left", "-6000px");     }   }   }else{   x.css("left", "-6000px");    }  }).blur(function(){   if(hint && text){   var blur_v = $.trim($(this).val());   if(blur_v === ""){    $(this).val(text);   }   }   $(this).css("color", bc).unbind("keyup").parent().css("z-index",0);   x.css("left", "-6000px");      });   //鼠標經過列表項事件  //鼠標經過  $(".mailHover").live("mouseover", function(){   index = Number($(this).attr("id").split("_")[1]);    liveValue = $("#mailList_"+index).text();   x.children("." + cf).removeClass(cf).addClass(cl);   $(this).addClass(cf).removeClass(cl);  });  });  x.bind("mousedown", function(){  that.val(liveValue);   }); }); }; })(jQuery);

<div class="reg_lin1"><div class="lin1_1">常用郵箱：</div><div class="lin1_2"><input type="text" class = "reg_text" id = "email" name = "email"/></div><div class="lin1_3"></div></div><script type="text/javascript">$("#email").mailAutoComplete({boxClass: "out_box", //外部box樣式listClass: "list_box", //默認的列表樣式focusClass: "focus_box", //列表選樣式中markCalss: "mark_box", //高亮樣式autoClass: false,textHint: true //提示文字自動隱藏});</script>

<!-- 郵箱自動提示的css --> <style type="text/css">  .out_box{border:1px solid #ccc; background:#fff; font:12px/20px Tahoma;}  .list_box{border-bottom:1px solid #eee; padding:0 5px; cursor:pointer;}  .focus_box{background:#f0f3f9;}  .mark_box{color:#c00;} </style>