JavaScript实现城市选择控件的效果

在淘宝旅行上看到的城市选择效果，感觉还不错，就自己的理解重新实现一遍，先看效果（有人说ie9下面有bug，lz用的是落后的xp，居然装不上ie9，去公司在搞搞好了），然后再细说实现原理，支持鼠标上下键选择城市，支持直接输入城市名称，拼音首字母，全拼，支持ie6遮盖select，压缩后12k。

实现的步骤：

一、先用一定的格式罗列出控件所需要的城市以及拼音等，我这里是按照如下格式罗列成一个数组, 如果需要增加城市，直接增加在数组里面即可：

城市我是一个一个手打的。。。

['北京|beijing|bj','上海|shanghai|sh', '重庆|chongqing|cq']

二、因为控件的城市分组按好几类划分，比如：按首字母hot 、abcdefh  、  ijklmnop  、 qrstuvwxyz 四组划分，

而划分了四组后又按照了首字母划分，所以我用正则表达式和循环把数组重新格式化为一个分组对象，热门城市取前16条。

对象格式如下：

{hot:{hot:[]},abcdefgh:{a:[1,2,3],b:[1,2,3]},ijklmnop:{i:[1.2.3],j:[1,2,3]},qrstuvwxyz:{}}

所用代码如下：

/* * 
 * 格式化城市数组为对象ocity，按照a-h,i-p,q-z,hot热门城市分组： 
 * {hot:{hot:[]},abcdefgh:{a:[1,2,3],b:[1,2,3]},ijklmnop:{i:[1.2.3],j:[1,2,3]},qrstuvwxyz:{}} 
 * */ 
 
(function () { 
 var citys = vcity.allcity, match, letter, 
  regex = vcity.regex, 
  reg2 = /^[a-h]$/i, reg3 = /^[i-p]$/i, reg4 = /^[q-z]$/i; 
 if (!vcity.ocity) { 
  vcity.ocity = {hot:{},abcdefgh:{}, ijklmnop:{}, qrstuvwxyz:{}}; 
  //console.log(citys.length); 
  for (var i = 0, n = citys.length; i < n; i++) { 
   match = regex.exec(citys[i]); 
   letter = match[3].touppercase(); 
   if (reg2.test(letter)) { 
    if (!vcity.ocity.abcdefgh[letter]) vcity.ocity.abcdefgh[letter] = []; 
    vcity.ocity.abcdefgh[letter].push(match[1]); 
   } else if (reg3.test(letter)) { 
    if (!vcity.ocity.ijklmnop[letter]) vcity.ocity.ijklmnop[letter] = []; 
    vcity.ocity.ijklmnop[letter].push(match[1]); 
   } else if (reg4.test(letter)) { 
    if (!vcity.ocity.qrstuvwxyz[letter]) vcity.ocity.qrstuvwxyz[letter] = []; 
    vcity.ocity.qrstuvwxyz[letter].push(match[1]); 
   } 
   /* 热门城市 前16条 */ 
   if(i<16){ 
    if(!vcity.ocity.hot['hot']) vcity.ocity.hot['hot'] = []; 
    vcity.ocity.hot['hot'].push(match[1]); 
   } 
  } 
 } 
})(); 

三、然后先照着淘宝旅行里面的样子弄出html与css；这里略过。

四、然后开始建立cityselector构造函数，根据城市对象，构建生成dom对象，在按照相应的事件触发。在生成相应的按照a\b\c\d……分组的时候遇到一个

关于排序的问题，我的对象格式是这样的abcdefgh:{a:[1,2,3],b:[1,2,3],c:[1,2,3]},里面的小数组要按照字母的顺序排序，但是我用for……in循环生成

出来是乱的，咨询了群里的高人后，处理方法如下：这里单独把key拿出来组成一个数组，然后排序后，在根据数组的值作为key值，来读取对象！

sortkey=[]; 
   for(ckey in ocity[key]){ 
    sortkey.push(ckey); 
    // ckey按照abcdedg顺序排序 
    sortkey.sort(); 
   } 
   for(var j=0,k = sortkey.length;j<k;j++){ 
    odl = document.createelement('dl'); 
    odt = document.createelement('dt'); 
    odd = document.createelement('dd'); 
    odt.innerhtml = sortkey[j] == 'hot'?' ':sortkey[j]; 
    odda = []; 
    for(var i=0,n=ocity[key][sortkey[j]].length;i<n;i++){ 
     str = '<a href="#">' + ocity[key][sortkey[j]][i] + '</a>'; 
     odda.push(str); 
    } 

五、鼠标上下键移动选择城市的处理方法：在城市弹出后记录一个this.count = 0；然后再获取上下键的按键事件中分别对count值加一或者减一，

当然count的最大值不能大于筛选出来的城市数组的长度，超过长度后归0，小于0后赋值最大值，然后把this.count的值，来作为数组的标获取相应的城市项：

switch(keycode){ 
   case 40: //向下箭头↓ 
    this.count++; 
    if(this.count > len-1) this.count = 0; 
    for(var i=0;i<len;i++){ 
     vcity._m.removeclass('on',lis[i]); 
    } 
    vcity._m.addclass('on',lis[this.count]); 
    break; 
   case 38: //向上箭头↑ 
    this.count--; 
    if(this.count<0) this.count = len-1; 
    for(i=0;i<len;i++){ 
     vcity._m.removeclass('on',lis[i]); 
    } 
    vcity._m.addclass('on',lis[this.count]); 
    break; 
   case 13: // enter键 
    this.input.value = vcity.regexchiese.exec(lis[this.count].innerhtml)[0]; 
    vcity._m.addclass('hide',this.ul); 
    vcity._m.addclass('hide',this.ul); 
    /* ie6 */ 
    vcity._m.addclass('hide',this.myiframe); 
    break; 
   default: 
    break; 
  } 

六、ie中对select的遮挡也是一个增加代码的地方，因为城市弹出框的大小是变化的，然后下拉的城市列也是根据筛选出来的值而变化，所以得每操作一个变化的地方的时候就重新给iframe设置长度和宽度，苦逼的处理方法啊，所以就多了这样一个方法，然后在改变尺寸的时候，应用一下就可以了。

/* ie6的改变遮罩select 的 iframe尺寸大小 */ 
 changeiframe:function(){ 
  if(!this.isie6)return; 
  this.myiframe.style.width = this.rootdiv.offsetwidth + 'px'; 
  this.myiframe.style.height = this.rootdiv.offsetheight + 'px'; 
 }

7、弹出框的取消问题，这个问题最开始我是设置document的click事件关闭层，然后再弹出的层上阻止click事件的冒泡，但是这样两个层有同时出现的可能，

// 设置点击文档隐藏弹出的城市选择框 
  vcity._m.on(document, 'click', function (event) { 
   event = vcity._m.getevent(event); 
   var target = vcity._m.gettarget(event); 
   if(target == that.input) return false; 
   //console.log(target.classname); 
   if (that.citybox)vcity._m.addclass('hide', that.citybox); 
   if (that.ul)vcity._m.addclass('hide', that.ul); 
   if(that.myiframe)vcity._m.addclass('hide',that.myiframe); 
  }); 

8、输入框输入拼音或者文字或者拼音首字母筛选城市，这个就是直接用正则表达式在最开始的数组里面筛选数据即可：

var reg = new regexp("^" + value + "|\\|" + value, 'gi');    
   var searchresult = []; 
   for (var i = 0, n = vcity.allcity.length; i < n; i++) { 
    if (reg.test(vcity.allcity[i])) { 
     var match = vcity.regex.exec(vcity.allcity[i]); 
     if (searchresult.length !== 0) { 
      str = '<li><b class="cityname">' + match[1] + '</b><b class="cityspell">' + match[2] + '</b></li>'; 
     } else { 
      str = '<li class="on"><b class="cityname">' + match[1] + '</b><b class="cityspell">' + match[2] + '</b></li>'; 
     } 
     searchresult.push(str); 
    } 
   }

然后总的js代码如下：

/* * 
 * ---------------------------------------- * 
 * 城市选择组件 v1.0 
 * author: vvg 
 * qq: 83816819 
 * mail: [e-mail] 
 * http://www.cnblogs.com/nnuf/ 
 * ---------------------------------------- * 
 * date: 2012-07-10 
 * ---------------------------------------- * 
 * */ 
 
/* * 
 * 全局空间 vcity 
 * */ 
var vcity = {}; 
/* * 
 * 静态方法集 
 * @name _m 
 * */ 
vcity._m = { 
 /* 选择元素 */ 
 $:function (arg, context) { 
  var tagall, n, eles = [], i, sub = arg.substring(1); 
  context = context || document; 
  if (typeof arg == 'string') { 
   switch (arg.charat(0)) { 
    case '#': 
     return document.getelementbyid(sub); 
     break; 
    case '.': 
     if (context.getelementsbyclassname) return context.getelementsbyclassname(sub); 
     tagall = vcity._m.$('*', context); 
     n = tagall.length; 
     for (i = 0; i < n; i++) { 
      if (tagall[i].classname.indexof(sub) > -1) eles.push(tagall[i]); 
     } 
     return eles; 
     break; 
    default: 
     return context.getelementsbytagname(arg); 
     break; 
   } 
  } 
 }, 
 
 /* 绑定事件 */ 
 on:function (node, type, handler) { 
  node.addeventlistener ? node.addeventlistener(type, handler, false) : node.attachevent('on' + type, handler); 
 }, 
 
 /* 获取事件 */ 
 getevent:function(event){ 
  return event || window.event; 
 }, 
 
 /* 获取事件目标 */ 
 gettarget:function(event){ 
  return event.target || event.srcelement; 
 }, 
 
 /* 获取元素位置 */ 
 getpos:function (node) { 
  var scrollx = document.documentelement.scrollleft || document.body.scrollleft, 
   scrollt = document.documentelement.scrolltop || document.body.scrolltop; 
  var pos = node.getboundingclientrect(); 
  return {top:pos.top + scrollt, right:pos.right + scrollx, bottom:pos.bottom + scrollt, left:pos.left + scrollx } 
 }, 
 
 /* 添加样式名 */ 
 addclass:function (c, node) { 
  if(!node)return; 
  node.classname = vcity._m.hasclass(c,node) ? node.classname : node.classname + ' ' + c ; 
 }, 
 
 /* 移除样式名 */ 
 removeclass:function (c, node) { 
  var reg = new regexp("(^|\\s+)" + c + "(\\s+|$)", "g"); 
  if(!vcity._m.hasclass(c,node))return; 
  node.classname = reg.test(node.classname) ? node.classname.replace(reg, '') : node.classname; 
 }, 
 
 /* 是否含有class */ 
 hasclass:function (c, node) { 
  if(!node || !node.classname)return false; 
  return node.classname.indexof(c)>-1; 
 }, 
 
 /* 阻止冒泡 */ 
 stoppropagation:function (event) { 
  event = event || window.event; 
  event.stoppropagation ? event.stoppropagation() : event.cancelbubble = true; 
 }, 
 /* 去除两端空格 */ 
 trim:function (str) { 
  return str.replace(/^\s+|\s+$/g,''); 
 } 
}; 
 
/* 所有城市数据,可以按照格式自行添加（北京|beijing|bj），前16条为热门城市 */ 
 
vcity.allcity = ['北京|beijing|bj','上海|shanghai|sh', '重庆|chongqing|cq', '深圳|shenzhen|sz', '广州|guangzhou|gz', '杭州|hangzhou|hz', 
 '南京|nanjing|nj', '苏州|shuzhou|sz', '天津|tianjin|tj', '成都|chengdu|cd', '南昌|nanchang|nc', '三亚|sanya|sy','青岛|qingdao|qd', 
 '厦门|xiamen|xm', '西安|xian|xa','长沙|changsha|cs','合肥|hefei|hf','*|xizang|xz', '内蒙古|neimenggu|nmg', '安庆|anqing|aq', '阿泰勒|ataile|atl', '安康|ankang|ak', 
 '阿克苏|akesu|aks', '包头|baotou|bt', '北海|beihai|bh', '百色|baise|bs','保山|baoshan|bs', '长治|changzhi|cz', '长春|changchun|cc', '常州|changzhou|cz', '昌都|changdu|cd', 
 '朝阳|chaoyang|cy', '常德|changde|cd', '长白山|changbaishan|cbs', '赤峰|chifeng|cf', '大同|datong|dt', '大连|dalian|dl', '达县|daxian|dx', '东营|dongying|dy', '大庆|daqing|dq', '丹东|dandong|dd', 
 '大理|dali|dl', '敦煌|dunhuang|dh', '鄂尔多斯|eerduosi|eeds', '恩施|enshi|es', '福州|fuzhou|fz', '阜阳|fuyang|fy', '贵阳|guiyang|gy', 
 '桂林|guilin|gl', '广元|guangyuan|gy', '格尔木|geermu|gem', '呼和浩特|huhehaote|hhht', '哈密|hami|hm', 
 '黑河|heihe|hh', '海拉尔|hailaer|hle', '哈尔滨|haerbin|heb', '海口|haikou|hk', '黄山|huangshan|hs', '邯郸|handan|hd', 
 '汉中|hanzhong|hz', '和田|hetian|ht', '晋江|jinjiang|jj', '锦州|jinzhou|jz', '景德镇|jingdezhen|jdz', 
 '嘉峪关|jiayuguan|jyg', '井冈山|jinggangshan|jgs', '济宁|jining|jn', '九江|jiujiang|jj', '佳木斯|jiamusi|jms', '济南|jinan|jn', 
 '喀什|kashi|ks', '昆明|kunming|km', '康定|kangding|kd', '克拉玛依|kelamayi|klmy', '库尔勒|kuerle|kel', '库车|kuche|kc', '兰州|lanzhou|lz', 
 '洛阳|luoyang|ly', '丽江|lijiang|lj', '林芝|linzhi|lz', '柳州|liuzhou|lz', '泸州|luzhou|lz', '连云港|lianyungang|lyg', '黎平|liping|lp', 
 '连成|liancheng|lc', '拉萨|lasa|ls', '临沧|lincang|lc', '临沂|linyi|ly', '芒市|mangshi|ms', '牡丹江|mudanjiang|mdj', '满洲里|manzhouli|mzl', '绵阳|mianyang|my', 
 '梅县|meixian|mx', '漠河|mohe|mh', '南充|nanchong|nc', '南宁|nanning|nn', '南阳|nanyang|ny', '南通|nantong|nt', '那拉提|nalati|nlt', 
 '宁波|ningbo|nb', '攀枝花|panzhihua|pzh', '衢州|quzhou|qz', '秦皇岛|qinhuangdao|qhd', '庆阳|qingyang|qy', '齐齐哈尔|qiqihaer|qqhe', 
 '石家庄|shijiazhuang|sjz', '沈阳|shenyang|sy', '思茅|simao|sm', '铜仁|tongren|tr', '塔城|tacheng|tc', '腾冲|tengchong|tc', '台州|taizhou|tz', 
 '通辽|tongliao|tl', '太原|taiyuan|ty', '威海|weihai|wh', '梧州|wuzhou|wz', '文山|wenshan|ws', '无锡|wuxi|wx', '潍坊|weifang|wf', '武夷山|*shan|wys', '乌兰浩特|wulanhaote|wlht', 
 '温州|wenzhou|wz', '乌鲁木齐|wulumuqi|wlmq', '万州|wanzhou|wz', '乌海|wuhai|wh', '兴义|xingyi|xy', '西昌|xichang|xc', '襄樊|xiangfan|xf', 
 '西宁|xining|xn', '锡林浩特|xilinhaote|xlht', '西双版纳|xishuangbanna|xsbn', '徐州|xuzhou|xz', '义乌|yiwu|yw', '永州|yongzhou|yz', '榆林|yulin|yl', '延安|yanan|ya', '运城|yuncheng|yc', 
 '烟台|yantai|yt', '银川|yinchuan|yc', '宜昌|yichang|yc', '宜宾|yibin|yb', '盐城|yancheng|yc', '延吉|yanji|yj', '玉树|yushu|ys', '伊宁|yining|yn', '珠海|zhuhai|zh', '昭通|zhaotong|zt', 
 '张家界|zhangjiajie|zjj', '舟山|zhoushan|zs', '郑州|zhengzhou|zz', '中卫|zhongwei|zw', '芷江|zhijiang|zj', '湛江|zhanjiang|zj']; 
 
/* 正则表达式 筛选中文城市名、拼音、首字母 */ 
 
vcity.regex = /^([\u4e00-\u9fa5\uf900-\ufa2d]+)\|(\w+)\|(\w)\w*$/i; 
vcity.regexchiese = /([\u4e00-\u9fa5\uf900-\ufa2d]+)/; 
 
/* * 
 * 格式化城市数组为对象ocity，按照a-h,i-p,q-z,hot热门城市分组： 
 * {hot:{hot:[]},abcdefgh:{a:[1,2,3],b:[1,2,3]},ijklmnop:{i:[1.2.3],j:[1,2,3]},qrstuvwxyz:{}} 
 * */ 
 
(function () { 
 var citys = vcity.allcity, match, letter, 
  regex = vcity.regex, 
  reg2 = /^[a-h]$/i, reg3 = /^[i-p]$/i, reg4 = /^[q-z]$/i; 
 if (!vcity.ocity) { 
  vcity.ocity = {hot:{},abcdefgh:{}, ijklmnop:{}, qrstuvwxyz:{}}; 
  //console.log(citys.length); 
  for (var i = 0, n = citys.length; i < n; i++) { 
   match = regex.exec(citys[i]); 
   letter = match[3].touppercase(); 
   if (reg2.test(letter)) { 
    if (!vcity.ocity.abcdefgh[letter]) vcity.ocity.abcdefgh[letter] = []; 
    vcity.ocity.abcdefgh[letter].push(match[1]); 
   } else if (reg3.test(letter)) { 
    if (!vcity.ocity.ijklmnop[letter]) vcity.ocity.ijklmnop[letter] = []; 
    vcity.ocity.ijklmnop[letter].push(match[1]); 
   } else if (reg4.test(letter)) { 
    if (!vcity.ocity.qrstuvwxyz[letter]) vcity.ocity.qrstuvwxyz[letter] = []; 
    vcity.ocity.qrstuvwxyz[letter].push(match[1]); 
   } 
   /* 热门城市 前16条 */ 
   if(i<16){ 
    if(!vcity.ocity.hot['hot']) vcity.ocity.hot['hot'] = []; 
    vcity.ocity.hot['hot'].push(match[1]); 
   } 
  } 
 } 
})(); 
/* 城市html模板 */ 
vcity._template = [ 
 '<p class="tip">热门城市(支持汉字/拼音)</p>', 
 '<ul>', 
 '<li class="on">热门城市</li>', 
 '<li>abcdefgh</li>', 
 '<li>ijklmnop</li>', 
 '<li>qrstuvwxyz</li>', 
 '</ul>' 
]; 
 
/* * 
 * 城市控件构造函数 
 * @cityselector 
 * */ 
 
vcity.cityselector = function () { 
 this.initialize.apply(this, arguments); 
}; 
 
vcity.cityselector.prototype = { 
 
 constructor:vcity.cityselector, 
 
 /* 初始化 */ 
 
 initialize :function (options) { 
  var input = options.input; 
  this.input = vcity._m.$('#'+ input); 
  this.inputevent(); 
 }, 
 
 /* * 
  * @createwarp 
  * 创建城市box html 框架 
  * */ 
 
 createwarp:function(){ 
  var inputpos = vcity._m.getpos(this.input); 
  var div = this.rootdiv = document.createelement('div'); 
  var that = this; 
 
  // 设置div阻止冒泡 
  vcity._m.on(this.rootdiv,'click',function(event){ 
   vcity._m.stoppropagation(event); 
  }); 
 
  // 设置点击文档隐藏弹出的城市选择框 
  vcity._m.on(document, 'click', function (event) { 
   event = vcity._m.getevent(event); 
   var target = vcity._m.gettarget(event); 
   if(target == that.input) return false; 
   //console.log(target.classname); 
   if (that.citybox)vcity._m.addclass('hide', that.citybox); 
   if (that.ul)vcity._m.addclass('hide', that.ul); 
   if(that.myiframe)vcity._m.addclass('hide',that.myiframe); 
  }); 
  div.classname = 'cityselector'; 
  div.style.position = 'absolute'; 
  div.style.left = inputpos.left + 'px'; 
  div.style.top = inputpos.bottom + 'px'; 
  div.style.zindex = 999999; 
 
  // 判断是否ie6，如果是ie6需要添加iframe才能遮住select框 
  var isie = (document.all) ? true : false; 
  var isie6 = this.isie6 = isie && !window.xmlhttprequest; 
  if(isie6){ 
   var myiframe = this.myiframe = document.createelement('iframe'); 
   myiframe.frameborder = '0'; 
   myiframe.src = 'about:blank'; 
   myiframe.style.position = 'absolute'; 
   myiframe.style.zindex = '-1'; 
   this.rootdiv.appendchild(this.myiframe); 
  } 
 
  var childdiv = this.citybox = document.createelement('div'); 
  childdiv.classname = 'citybox'; 
  childdiv.id = 'citybox'; 
  childdiv.innerhtml = vcity._template.join(''); 
  var hotcity = this.hotcity = document.createelement('div'); 
  hotcity.classname = 'hotcity'; 
  childdiv.appendchild(hotcity); 
  div.appendchild(childdiv); 
  this.createhotcity(); 
 }, 
 
 /* * 
  * @createhotcity 
  * tab下面div：hot,a-h,i-p,q-z 分类html生成，dom操作 
  * {hot:{hot:[]},abcdefgh:{a:[1,2,3],b:[1,2,3]},ijklmnop:{},qrstuvwxyz:{}} 
  **/ 
 
 createhotcity:function(){ 
  var odiv,odl,odt,odd,odda=[],str,key,ckey,sortkey,regex = vcity.regex, 
   ocity = vcity.ocity; 
  for(key in ocity){ 
   odiv = this[key] = document.createelement('div'); 
   // 先设置全部隐藏hide 
   odiv.classname = key + ' ' + 'citytab hide'; 
   sortkey=[]; 
   for(ckey in ocity[key]){ 
    sortkey.push(ckey); 
    // ckey按照abcdedg顺序排序 
    sortkey.sort(); 
   } 
   for(var j=0,k = sortkey.length;j<k;j++){ 
    odl = document.createelement('dl'); 
    odt = document.createelement('dt'); 
    odd = document.createelement('dd'); 
    odt.innerhtml = sortkey[j] == 'hot'?' ':sortkey[j]; 
    odda = []; 
    for(var i=0,n=ocity[key][sortkey[j]].length;i<n;i++){ 
     str = '<a href="javascript:">' + ocity[key][sortkey[j]][i] + '</a>'; 
     odda.push(str); 
    } 
    odd.innerhtml = odda.join(''); 
    odl.appendchild(odt); 
    odl.appendchild(odd); 
    odiv.appendchild(odl); 
   } 
 
   // 移除热门城市的隐藏css 
   vcity._m.removeclass('hide',this.hot); 
   this.hotcity.appendchild(odiv); 
  } 
  document.body.appendchild(this.rootdiv); 
  /* ie6 */ 
  this.changeiframe(); 
 
  this.tabchange(); 
  this.linkevent(); 
 }, 
 
 /* * 
  * tab按字母顺序切换 
  * @ tabchange 
  * */ 
 
 tabchange:function(){ 
  var lis = vcity._m.$('li',this.citybox); 
  var divs = vcity._m.$('div',this.hotcity); 
  var that = this; 
  for(var i=0,n=lis.length;i<n;i++){ 
   lis[i].index = i; 
   lis[i].onclick = function(){ 
    for(var j=0;j<n;j++){ 
     vcity._m.removeclass('on',lis[j]); 
     vcity._m.addclass('hide',divs[j]); 
    } 
    vcity._m.addclass('on',this); 
    vcity._m.removeclass('hide',divs[this.index]); 
    /* ie6 改变tab的时候 改变iframe 大小*/ 
    that.changeiframe(); 
   }; 
  } 
 }, 
 
 /* * 
  * 城市link事件 
  * @linkevent 
  * */ 
 
 linkevent:function(){ 
  var links = vcity._m.$('a',this.hotcity); 
  var that = this; 
  for(var i=0,n=links.length;i<n;i++){ 
   links[i].onclick = function(){ 
    that.input.value = this.innerhtml; 
    vcity._m.addclass('hide',that.citybox); 
    /* 点击城市名的时候隐藏myiframe */ 
    vcity._m.addclass('hide',that.myiframe); 
   } 
  } 
 }, 
 
 /* * 
  * input城市输入框事件 
  * @inputevent 
  * */ 
 
 inputevent:function(){ 
  var that = this; 
  vcity._m.on(this.input,'click',function(event){ 
   event = event || window.event; 
   if(!that.citybox){ 
    that.createwarp(); 
   }else if(!!that.citybox && vcity._m.hasclass('hide',that.citybox)){ 
    // slideul 不存在或者 slideul存在但是是隐藏的时候 两者不能共存 
    if(!that.ul || (that.ul && vcity._m.hasclass('hide',that.ul))){ 
     vcity._m.removeclass('hide',that.citybox); 
 
     /* ie6 移除iframe 的hide 样式 */ 
     //alert('click'); 
     vcity._m.removeclass('hide',that.myiframe); 
     that.changeiframe(); 
    } 
   } 
  }); 
  vcity._m.on(this.input,'focus',function(){ 
   that.input.select(); 
   if(that.input.value == '城市名') that.input.value = ''; 
  }); 
  vcity._m.on(this.input,'blur',function(){ 
   if(that.input.value == '') that.input.value = '城市名'; 
  }); 
  vcity._m.on(this.input,'keyup',function(event){ 
   event = event || window.event; 
   var keycode = event.keycode; 
   vcity._m.addclass('hide',that.citybox); 
   that.createul(); 
 
   /* 移除iframe 的hide 样式 */ 
   vcity._m.removeclass('hide',that.myiframe); 
 
   // 下拉菜单显示的时候捕捉按键事件 
   if(that.ul && !vcity._m.hasclass('hide',that.ul) && !that.isempty){ 
    that.keyboardevent(event,keycode); 
   } 
  }); 
 }, 
 
 /* * 
  * 生成下拉选择列表 
  * @ createul 
  * */ 
 
 createul:function () { 
  //console.log('createul'); 
  var str; 
  var value = vcity._m.trim(this.input.value); 
  // 当value不等于空的时候执行 
  if (value !== '') { 
   var reg = new regexp("^" + value + "|\\|" + value, 'gi'); 
   var searchresult = []; 
   for (var i = 0, n = vcity.allcity.length; i < n; i++) { 
    if (reg.test(vcity.allcity[i])) { 
     var match = vcity.regex.exec(vcity.allcity[i]); 
     if (searchresult.length !== 0) { 
      str = '<li><b class="cityname">' + match[1] + '</b><b class="cityspell">' + match[2] + '</b></li>'; 
     } else { 
      str = '<li class="on"><b class="cityname">' + match[1] + '</b><b class="cityspell">' + match[2] + '</b></li>'; 
     } 
     searchresult.push(str); 
    } 
   } 
   this.isempty = false; 
   // 如果搜索数据为空 
   if (searchresult.length == 0) { 
    this.isempty = true; 
    str = '<li class="empty">对不起，没有找到数据 "<em>' + value + '</em>"</li>'; 
    searchresult.push(str); 
   } 
   // 如果slideul不存在则添加ul 
   if (!this.ul) { 
    var ul = this.ul = document.createelement('ul'); 
    ul.classname = 'cityslide'; 
    this.rootdiv && this.rootdiv.appendchild(ul); 
    // 记录按键次数，方向键 
    this.count = 0; 
   } else if (this.ul && vcity._m.hasclass('hide', this.ul)) { 
    this.count = 0; 
    vcity._m.removeclass('hide', this.ul); 
   } 
   this.ul.innerhtml = searchresult.join(''); 
 
   /* ie6 */ 
   this.changeiframe(); 
 
   // 绑定li事件 
   this.lievent(); 
  }else{ 
   vcity._m.addclass('hide',this.ul); 
   vcity._m.removeclass('hide',this.citybox); 
 
   vcity._m.removeclass('hide',this.myiframe); 
 
   this.changeiframe(); 
  } 
 }, 
 
 /* ie6的改变遮罩select 的 iframe尺寸大小 */ 
 changeiframe:function(){ 
  if(!this.isie6)return; 
  this.myiframe.style.width = this.rootdiv.offsetwidth + 'px'; 
  this.myiframe.style.height = this.rootdiv.offsetheight + 'px'; 
 }, 
 
 /* * 
  * 特定键盘事件，上、下、enter键 
  * @ keyboardevent 
  * */ 
 
 keyboardevent:function(event,keycode){ 
  var lis = vcity._m.$('li',this.ul); 
  var len = lis.length; 
  switch(keycode){ 
   case 40: //向下箭头↓ 
    this.count++; 
    if(this.count > len-1) this.count = 0; 
    for(var i=0;i<len;i++){ 
     vcity._m.removeclass('on',lis[i]); 
    } 
    vcity._m.addclass('on',lis[this.count]); 
    break; 
   case 38: //向上箭头↑ 
    this.count--; 
    if(this.count<0) this.count = len-1; 
    for(i=0;i<len;i++){ 
     vcity._m.removeclass('on',lis[i]); 
    } 
    vcity._m.addclass('on',lis[this.count]); 
    break; 
   case 13: // enter键 
    this.input.value = vcity.regexchiese.exec(lis[this.count].innerhtml)[0]; 
    vcity._m.addclass('hide',this.ul); 
    vcity._m.addclass('hide',this.ul); 
    /* ie6 */ 
    vcity._m.addclass('hide',this.myiframe); 
    break; 
   default: 
    break; 
  } 
 }, 
 
 /* * 
  * 下拉列表的li事件 
  * @ lievent 
  * */ 
 
 lievent:function(){ 
  var that = this; 
  var lis = vcity._m.$('li',this.ul); 
  for(var i = 0,n = lis.length;i < n;i++){ 
   vcity._m.on(lis[i],'click',function(event){ 
    event = vcity._m.getevent(event); 
    var target = vcity._m.gettarget(event); 
    that.input.value = vcity.regexchiese.exec(target.innerhtml)[0]; 
    vcity._m.addclass('hide',that.ul); 
    /* ie6 下拉菜单点击事件 */ 
    vcity._m.addclass('hide',that.myiframe); 
   }); 
   vcity._m.on(lis[i],'mouseover',function(event){ 
    event = vcity._m.getevent(event); 
    var target = vcity._m.gettarget(event); 
    vcity._m.addclass('on',target); 
   }); 
   vcity._m.on(lis[i],'mouseout',function(event){ 
    event = vcity._m.getevent(event); 
    var target = vcity._m.gettarget(event); 
    vcity._m.removeclass('on',target); 
   }) 
  } 
 } 
}; 

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。