1. 添加动态加载css文件 不需要引入css css全部在JS动态生成。
2. 不需要额外的标签 只需要一个input输入框 并且默认指定一个class类名为 "inputElem" 当然也可以自己配置参数 还需要一个当前父级容器增加一个默认类名 parentCls(也可以自己配置)，因为输入框匹配值后需要一个隐藏域 所以需要隐藏域增加一个class "hiddenCls" 当然也支持自己配置参数。

如下代码：

复制代码 代码如下:
<div class="parentCls">
        <div style="width:200px;height:26px;border:1px solid #ccc;">
            <input type="text" class="inputElem" style="width:200px;height:26px;line-height:26px;"/>
        </div>
        <input type="hidden" class="hiddenCls"/>
    </div>

    <div class="parentCls">
        <div style="width:200px;height:26px;border:1px solid #ccc;">
            <input type="text" class="inputElem" style="width:200px;height:26px;line-height:26px;"/>
        </div>
        <input type="hidden" class="hiddenCls"/>
    </div>

3. 支持页面上有多个输入框。

4. 支持鼠标点击和 键盘 上移和下移键操作 类似于百度输入框。
页面上所有的标签都是动态的生成的，不需要额外的标签。如上面的 只需要input标签 其他的div标签不依赖 只需要父级元素增加class "parentCls"（当然可以自己配置类名），
及要传给后台开发人员的隐藏域输入框 增加一个class "hiddenCls" 当然也可以自动配置参数。

我的模糊查询匹配的需求是这样的：
1. 每keyup时候 点击或者键盘上移下移操作 输入框填充用户名/工号 隐藏域填充工号 发请求 服务器返回数据 渲染出来。当然 隐藏域填充工号 值是form表单提交时候 后台要拿到提交过来的工号 所以需要这么一个隐藏域。
2. 当用户直接在输入框输入值时候 并没有键盘上移下移 或者 点击下拉框某一项时候 当鼠标失去焦点时候(blur) 当前输入框值为空 隐藏域值为空，这样做的目的 是为了防止上次form提交过后的数据仍然保存在隐藏域里面 当用户重新输入的时候 用户也并没有操作键盘上下移操作或者点击操作 再点击提交按钮时(失去焦点)，那么值为空 隐藏域值为空 这样防止搜索出来不是用户输入的那个东东。
3. 当用户点击某一项时候 或者 上移下移时候 输入框动态的生成值 且输入框值现在不能重新输入 只有当点击输入框x的时候 才可以重新输入。
4. 已经遗留输入框可以多选的接口 目前还未完善输入框多选的操作。
5. 禁止ctrl+v 或者右键 粘贴操作。

下面HTML代码如下：

复制代码 代码如下:
<div class="parentCls">
        <div style="width:200px;height:26px;border:1px solid #ccc;">
            <input type="text" class="inputElem" style="width:200px;height:26px;line-height:26px;"/>
        </div>
        <input type="hidden" class="hiddenCls"/>
    </div>

    <div class="parentCls">
        <div style="width:200px;height:26px;border:1px solid #ccc;">
            <input type="text" class="inputElem" style="width:200px;height:26px;line-height:26px;"/>
        </div>
        <input type="hidden" class="hiddenCls"/>
    </div>

    <input type="button" value="提交"/>

JS代码如下：

复制代码 代码如下:
/**
 * JS 模糊查询
 * @author tugenhua
 * @date 2013-11-19
 * @param 1.当前的input add targetCls
 * 2. 隐藏域里面统一增加同类名 叫 hiddenCls
 * 3. 在各个父级元素上 添加类名 parentCls
 */

 function AutoComplete (options) {
     this.config = {
        targetCls          : '.inputElem',          // 输入框目标元素
        parentCls          : '.parentCls',          // 父级类
        hiddenCls          : '.hiddenCls',          // 隐藏域input
        searchForm         :'.jqtransformdone',     //form表单
        hoverBg            : 'hoverBg',             // 鼠标移上去的背景
        outBg              : 'outBg',               // 鼠标移下拉的背景
        isSelectHide       : true,                 // 点击下拉框 是否隐藏
        url                : '',                    // url接口
        height             : 0,                     // 默认为0 不设置的话 那么高度自适应
        manySelect         : false,                 // 输入框是否多选 默认false 单选
        renderHTMLCallback : null,                  // keyup时 渲染数据后的回调函数
        callback           : null,                  // 点击某一项 提供回调
        closedCallback     : null                   // 点击输入框某一项x按钮时 回调函数
     };

     this.cache = {
        currentIndex        : -1,
        oldIndex            : -1,
        inputArrs           : []                 // 多选时候 输入框值放到数组里面去
     };
     this.init(options);
 }

 AutoComplete.prototype = {

    constructor: AutoComplete,
    init: function(options) {

        this.config = $.extend(this.config, options || {});
        var self = this,
            _config = self.config,
            _cache = self.cache;

         // 鼠标点击输入框时候
          $(_config.targetCls).each(function(index,item) {

              /*
               *  禁止 ctrl+v 和 黏贴事件
               */
              $(item).unbind('paste');
              $(item).bind('paste',function(e){
                  e.preventDefault();
                  var target = e.target,
                      targetParent = $(target).closest(_config.parentCls);
                  $(this).val('');
                  $(_config.hiddenCls,targetParent) && $(_config.hiddenCls,targetParent).val('');
              });

              $(item).keyup(function(e){
                  _cache.inputArrs = [];
                  var targetVal = $.trim($(this).val()),
                      keyCode = e.keyCode,
                      elemHeight = $(this).outerHeight(),
                      elemWidth = $(this).outerWidth();

                  // 如果输入框值为空的话 那么隐藏域的value清空掉
                  if(targetVal == '') {
                       var curParents = $(this).closest(_config.parentCls);
                       $(_config.hiddenCls,curParents).val('');
                  }
                  var targetParent = $(this).parent();
                  $(targetParent).css({'position':'relative'});

                  if($('.auto-tips',targetParent).length == 0) {
                      // 初始化时候 动态创建下拉框容器
                     $(targetParent).append($('<div class="auto-tips hidden"></div>'));
                     $('.auto-tips',targetParent).css({'position':'absolute','top':elemHeight,'left':'0px','z-index':999,'width':elemWidth,'border':'1px solid #ccc'});
                  }

                 
                  var curIndex = self._keyCode(keyCode);
                  if(curIndex > -1){
                          self._keyUpAndDown(targetVal,e,targetParent);
                    }else {
                         if(targetVal != '') {
                            self._doPostAction(targetVal,targetParent);
                         }

                    }
              });

              // 失去焦点时 如果没有点击 或者上下移时候 直接输入 那么当前输入框值情况 隐藏域值情况
              $(item).blur(function(e){
                  var target = e.target,
                      targetParent = $(target).closest(_config.parentCls);
                  if($(this).attr('up') || $(this).attr('down')) {
                     return;
                  }else {
                     $(this).val('');
                     $(_config.hiddenCls,targetParent).val('');
                  }
              });

          });

          // 阻止form表单默认enter键提交
          $(_config.searchForm).each(function(index,item) {
               $(item).keydown(function(e){
                    var keyCode = e.keyCode;
                    if(keyCode == 13) {
                        return false;
                    }
               });
          });

          // 点击文档
          $(document).click(function(e){
             e.stopPropagation();
             var target = e.target,
                 tagParent = $(target).parent(),
                 attr = $(target,tagParent).closest('.auto-tips');

             var tagCls = _config.targetCls.replace(/^\./,'');

             if(attr.length > 0 || $(target,tagParent).hasClass(tagCls)) {
                return;
             }else {
                $('.auto-tips').each(function(index,item){
                    !$(item,tagParent).hasClass('hidden') && $(item,tagParent).addClass('hidden');
                });

             }
          });

          var stylesheet = '.auto-tips { margin: 0 1px; list-style: none;height:auto !important;padding: 0px;position:absolute; border:1px solid #ccc; top:27px; left:0; z-index:999; width:100%;background:#fff !important;}' +
                           '.auto-tips p {overflow: hidden;margin: 1px 0;padding: 5px 5px;border-bottom: 1px solid #e7e7e7;color: #666;text-decoration: none;line-height: 23px;white-space: nowrap;cursor: pointer;zoom: 1;}' +
                           '.auto-tips p img{ vertical-align:middle;float:left;}' +
                           '.create-input{line-height:26px,padding-left:3px;}' +
                           '.create-input span{margin-top:1px;height:24px;float:left;}' +
                           '.create-input span i,.auto-tips span a{font-style:normal;float:left;cursor:default;}' +
                           '.create-input span a{padding:0 8px 0 3px;cursor:pointer;}' +
                           '.auto-tips p.hoverBg {background-color: #669cb6;color: #fff;cursor: pointer;}' +
                           '.hidden {display:none;}';

          this._addStyleSheet(stylesheet);

    },
    /**
     * 键盘上下键操作
     */
    _keyUpAndDown: function(targetVal,e,targetParent) {
        var self = this,
            _cache = self.cache,
            _config = self.config;

        // 如果请求成功后 返回了数据(根据元素的长度来判断) 执行以下操作
        if($('.auto-tips p',targetParent) && $('.auto-tips p',targetParent).length > 0) {

            var plen = $('.auto-tips p',targetParent).length,
                keyCode = e.keyCode;
                _cache.oldIndex = _cache.currentIndex;

            // 上移操作
            if(keyCode == 38) {
                if(_cache.currentIndex == -1) {
                    _cache.currentIndex = plen - 1;
                }else {
                    _cache.currentIndex = _cache.currentIndex - 1;
                    if(_cache.currentIndex < 0) {
                        _cache.currentIndex = plen - 1;
                    }
                }
                if(_cache.currentIndex !== -1) {

                    !$('.auto-tips .p-index'+_cache.currentIndex,targetParent).hasClass(_config.hoverBg) &&
                    $('.auto-tips .p-index'+_cache.currentIndex,targetParent).addClass(_config.hoverBg).siblings().removeClass(_config.hoverBg);
                    var curAttr = $('.auto-tips .p-index'+_cache.currentIndex,targetParent).attr('data-html'),
                        embId = $('.auto-tips .p-index'+_cache.currentIndex,targetParent).attr('embId');

                    // 判断是否是多选操作 多选操作 暂留接口
                    if(_config.manySelect) {
                        _cache.inputArrs.push(curAttr);
                        _cache.inputArrs = self._unique(_cache.inputArrs);
                        self._manySelect(targetParent);
                    }else {
                        $(_config.targetCls,targetParent).val(curAttr);
                        // 上移操作增加一个属性 当失去焦点时候 判断有没有这个属性
                        if(!$(_config.targetCls,targetParent).attr('up')){
                            $(_config.targetCls,targetParent).attr('up','true');
                        }
                       

                        var pCls = $(_config.targetCls,targetParent).closest(_config.parentCls);
                        $(_config.hiddenCls,pCls).val(embId);

                        self._createDiv(targetParent,curAttr);
                        self._closed(targetParent);
                        // hover
                        self._hover(targetParent);
                    }

                }

            }else if(keyCode == 40) { //下移操作
                if(_cache.currentIndex == plen - 1) {
                    _cache.currentIndex = 0;
                }else {
                    _cache.currentIndex++;
                    if(_cache.currentIndex > plen - 1) {
                        _cache.currentIndex = 0;
                    }
                }
                if(_cache.currentIndex !== -1) {

                    !$('.auto-tips .p-index'+_cache.currentIndex,targetParent).hasClass(_config.hoverBg) &&
                    $('.auto-tips .p-index'+_cache.currentIndex,targetParent).addClass(_config.hoverBg).siblings().removeClass(_config.hoverBg);
                    var curAttr = $('.auto-tips .p-index'+_cache.currentIndex,targetParent).attr('data-html'),
                        embId = $('.auto-tips .p-index'+_cache.currentIndex,targetParent).attr('embId');

                   
                    // 判断是否是多选操作 多选操作 暂留接口
                    if(_config.manySelect) {
                        _cache.inputArrs.push(curAttr);
                        _cache.inputArrs = self._unique(_cache.inputArrs);
                        self._manySelect(targetParent);
                    }else {
                        $(_config.targetCls,targetParent).val(curAttr);

                        // 下移操作增加一个属性 当失去焦点时候 判断有没有这个属性
                        if(!$(_config.targetCls,targetParent).attr('down')){
                            $(_config.targetCls,targetParent).attr('down','true');
                        }

                        var pCls = $(_config.targetCls,targetParent).closest(_config.parentCls);
                        $(_config.hiddenCls,pCls).val(embId);
                        self._createDiv(targetParent,curAttr);
                        self._closed(targetParent);
                        // hover
                        self._hover(targetParent);
                    }

                }
            }else if(keyCode == 13) { //回车操作
                var curVal = $('.auto-tips .p-index'+_cache.oldIndex,targetParent).attr('data-html');
                $(_config.targetCls,targetParent).val(curVal);
                if(_config.isSelectHide) {
                    !$(".auto-tips",targetParent).hasClass('hidden') && $(".auto-tips",targetParent).addClass('hidden');
                }

                _cache.currentIndex = -1;
                _cache.oldIndex = -1;

            }
        }
    },
    // 键码判断
    _keyCode: function(code) {
        var arrs = ['17','18','38','40','37','39','33','34','35','46','36','13','45','44','145','19','20','9'];
        for(var i = 0, ilen = arrs.length; i < ilen; i++) {
            if(code == arrs[i]) {
                return i;
            }
        }
        return -1;
    },
    _doPostAction: function(targetVal,targetParent) {

        var  self = this,
             _cache = self.cache,
             _config = self.config,
             url = _config.url;

        // 假如返回的数据如下：
        var results = [{lastName:'tugenhua',emplId:'E0987',image:''},{lastName:'tugenhua',emplId:'E0988',image:''},{lastName:'tugenhua',emplId:'E0989',image:''}];
        self._renderHTML(results,targetParent);
        self._executeClick(results,targetParent);
       /** $.get(url+"?keyword="+targetVal+"&timestamp="+new Date().getTime(),function(data){
            var ret = $.parseJSON(data.content),
                results = ret.results;
            if(results.length > 0) {
                self._renderHTML(results,targetParent);
                self._executeClick(results,targetParent);
            }else {
                !$('.auto-tips',targetParent).hasClass('hidden') && $('.auto-tips',targetParent).addClass("hidden");
                $('.auto-tips',targetParent).html('');

            }
        });**/

    },
    _renderHTML: function(ret,targetParent) {
        var self = this,
            _config = self.config,
            _cache = self.cache,
            html = '';

        for(var i = 0, ilen = ret.length; i < ilen; i+=1) {
            html += '<p  data-html = "'+ret[i].lastName+'('+ret[i].emplId+')" embId="'+ret[i].emplId+'" class="p-index'+i+'">' +
                       '<img src="/UploadFiles/2021-04-02/'+ret[i].image+'">                       '<span>'+ret[i].lastName+'('+ret[i].emplId+')</span>' +
                    '</p>';
        }
        // 渲染值到下拉框里面去
        $('.auto-tips',targetParent).html(html);
         $('.auto-tips',targetParent).hasClass('hidden') && $('.auto-tips',targetParent).removeClass('hidden');
        $('.auto-tips p:last',targetParent).css({"border-bottom":'none'});

        _config.renderHTMLCallback && $.isFunction(_config.renderHTMLCallback) && _config.renderHTMLCallback();

        // 出现滚动条 计算p的长度 * 一项p的高度 是否大于 设置的高度 如是的话 出现滚动条 反之
        var plen = $('.auto-tips p',targetParent).length,
            pheight = $('.auto-tips p',targetParent).height();

        if(_config.height > 0) {
            if(plen*pheight > _config.height) {
                $('.auto-tips',targetParent).css({'height':_config.height,'overflow':'auto'});
            }else {
                $('.auto-tips',targetParent).css({'height':'auto','overflow':'auto'});
            }
        }
    },
    /**
      * 当数据相同的时 点击对应的项时 返回数据
      */
    _executeClick: function(ret,targetParent) {
        var self = this,
            _config = self.config,
            _cache = self.cache;
         $('.auto-tips p',targetParent).unbind('click');
         $('.auto-tips p',targetParent).bind('click',function(e){
              var dataAttr = $(this).attr('data-html'),
                  embId = $(this).attr('embId');

              // 判断是否多选
              if(_config.manySelect) {
                  _cache.inputArrs.push(dataAttr);
                  _cache.inputArrs = self._unique(_cache.inputArrs);
                  self._manySelect(targetParent);
              }else {
                 $(_config.targetCls,targetParent).val(dataAttr);
                 var parentCls = $(_config.targetCls,targetParent).closest(_config.parentCls),
                     hiddenCls = $(_config.hiddenCls,parentCls);
                 $(hiddenCls).val(embId);
                 self._createDiv(targetParent,dataAttr);

                 // hover
                 self._hover(targetParent);

                 !$(_config.targetCls,targetParent).hasClass('hidden') && $(_config.targetCls,targetParent).addClass('hidden');
              }
              self._closed(targetParent);
              if(_config.isSelectHide) {
                  !$('.auto-tips',targetParent).hasClass('hidden') && $('.auto-tips',targetParent).addClass('hidden');
              }
              _config.callback && $.isFunction(_config.callback) && _config.callback();
         });

         // 鼠标移上效果
         $('.auto-tips p',targetParent).hover(function(e){
             !$(this,targetParent).hasClass(_config.hoverBg) &&
             $(this,targetParent).addClass(_config.hoverBg).siblings().removeClass(_config.hoverBg);
         });
    },
    _hover: function(targetParent){
        $('.create-input span',targetParent).hover(function(){
            $(this).css({"background":'#ccc','padding-left':'0px'});
        },function(){
             $(this).css({"background":''});
        });
    },
    // 动态的创建div标签 遮住input输入框
    _createDiv: function(targetParent,dataAttr){
         var self = this,
             _config = self.config;
         var iscreate = $('.create-input',targetParent);

         // 确保只创建一次div
         if(iscreate.length > 0) {
            $('.create-input',targetParent).remove();
         }
         $(targetParent).prepend($('<div class="create-input"><span><i></i></span></div>'));
         $('.create-input span i',targetParent).html(dataAttr);
         $(_config.targetCls,targetParent).val(dataAttr);
         $('.create-input span',targetParent).append('<a class="alink">X</a>');
         $('.alink',targetParent).css({'float':'left','background':'none'});
    },
    // X 关闭事件
    _closed: function(targetParent){
         var self = this,
             _config = self.config;
         /*
          * 点击X 关闭按钮
          * 判断当前输入框有没有up和down属性 有的话 删除掉 否则 什么都不做
          */
          $('.alink',targetParent).click(function(){
             $('.create-input',targetParent) && $('.create-input',targetParent).remove();
             $(_config.targetCls,targetParent) && $(_config.targetCls,targetParent).hasClass('hidden') &&
             $(_config.targetCls,targetParent).removeClass('hidden');
             $(_config.targetCls,targetParent).val('');
             //清空隐藏域的值
             var curParent = $(_config.targetCls,targetParent).closest(_config.parentCls);
             $(_config.hiddenCls,curParent).val('');

             var targetInput = $(_config.targetCls,targetParent);
             if($(targetInput).attr('up') || $(targetInput).attr('down')) {
                 $(targetInput).attr('up') && $(targetInput).removeAttr('up');
                 $(targetInput).attr('down') && $(targetInput).removeAttr('down');
             }
             _config.closedCallback && $.isFunction(_config.closedCallback) && _config.closedCallback();
          });
    },
    /*
     * 数组去重复
     */
    _unique: function(arrs) {
        var obj = {},
            newArrs = [];
        for(var i = 0, ilen = arrs.length; i < ilen; i++) {
            if(obj[arrs[i]] != 1) {
                newArrs.push(arrs[i]);
                obj[arrs[i]] = 1;
            }
        }
        return newArrs;
    },
    /*
     * 输入框多选操作
     */
    _manySelect: function(targetParent) {
        var self = this,
            _config = self.config,
            _cache = self.cache;
        if(_cache.inputArrs.length > 0) {
            $(_config.targetCls,targetParent).val(_cache.inputArrs.join(','));
        }
    },
    /*
     * 判断是否是string
     */
     _isString: function(str) {
        return Object.prototype.toString.apply(str) === '[object String]';
     },
    /*
     * JS 动态添加css样式
     */
    _addStyleSheet: function(refWin, cssText, id){

        var self = this;
        if(self._isString(refWin)) {
            id = cssText;
            cssText = refWin;
            refWin = window;
        }
        refWin = $(refWin);
        var doc = document;
        var elem;

        if (id && (id = id.replace('#', ''))) {
            elem = $('#' + id, doc);
        }

        // 仅添加一次，不重复添加
        if (elem) {
            return;
        }
       //elem = $('<style></style>'); 不能这样创建 IE8有bug
        elem =  document.createElement("style");
        // 先添加到 DOM 树中，再给 cssText 赋值，否则 css hack 会失效
        $('head', doc).append(elem);

        if (elem.styleSheet) { // IE
            elem.styleSheet.cssText = cssText;
        } else { // W3C
            elem.appendChild(doc.createTextNode(cssText));
        }
    },
    /*
     * 销毁操作 释放内存
     */
    destory: function() {
        var self = this,
            _config = self.config,
            _cache = self.cache;
        _cache.ret  = [];
        _cache.currentIndex = 0;
        _cache.oldIndex = 0;
        _cache.inputArrs = [];
        _config.targetCls = null;
    }
 };
 // 初始化
 $(function(){
    var auto = new AutoComplete({
       // url: '/rocky/commonservice/user/find.json'
    });
 });