新建index.html文件，直接复制下面代码到新建的文件index.html里面，用浏览器访问，仅用于参考:
<!doctype html>
<html><meta charset="utf-8"><style>body { margin-left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px;}.auto_hidden { width:204px;border-top: 1px solid #333; border-bottom: 1px solid #333; border-left: 1px solid #333; border-right: 1px solid #333; position:absolute; display:none;}.auto_show { width:204px; border-top: 1px solid #333; border-bottom: 1px solid #333; border-left: 1px solid #333; border-right: 1px solid #333; position:absolute; z-index:9999; /* 设置对象的层叠顺序 */ display:block;}.auto_onmouseover{ color:#ffffff; background-color:highlight; width:100%;}.auto_onmouseout{ color:#000000; width:100%; background-color:#ffffff;}</style><script language="javascript"><!--var $ = function (id) { return "string" == typeof id ? document.getElementById(id) : id;}var Bind = function(object, fun) { return function() { return fun.apply(object, arguments); }}function AutoComplete(obj,autoObj,arr){ this.obj=$(obj); //输入框 this.autoObj=$(autoObj);//DIV的根节点 this.value_arr=arr; //不要包含重复值 this.index=-1; //当前选中的DIV的索引 this.search_value=""; //保存当前搜索的字符}AutoComplete.prototype={ //初始化DIV的位置 init: function(){ this.autoObj.style.left = this.obj.offsetLeft + "px"; this.autoObj.style.top = this.obj.offsetTop + this.obj.offsetHeight + "px"; this.autoObj.style.width= this.obj.offsetWidth - 2 + "px";//减去边框的长度2px }, //删除自动完成需要的所有DIV deleteDIV: function(){ while(this.autoObj.hasChildNodes()){ this.autoObj.removeChild(this.autoObj.firstChild); } this.autoObj.className="auto_hidden"; }, //设置值 setValue: function(_this){ return function(){ _this.obj.value=this.seq; _this.autoObj.className="auto_hidden"; } }, //模拟鼠标移动至DIV时，DIV高亮 autoOnmouseover: function(_this,_div_index){ return function(){ _this.index=_div_index; var length = _this.autoObj.children.length; for(var j=0;j<length;j++){ if(j!=_this.index ){ _this.autoObj.childNodes[j].className='auto_onmouseout'; }else{ _this.autoObj.childNodes[j].className='auto_onmouseover'; } } } }, //更改classname changeClassname: function(length){ for(var i=0;i<length;i++){ if(i!=this.index ){ this.autoObj.childNodes[i].className='auto_onmouseout'; }else{ this.autoObj.childNodes[i].className='auto_onmouseover'; this.obj.value=this.autoObj.childNodes[i].seq; } } } , //响应键盘 pressKey: function(event){ var length = this.autoObj.children.length; //光标键"↓" if(event.keyCode==40){ ++this.index; if(this.index>length){ this.index=0; }else if(this.index==length){ this.obj.value=this.search_value; } this.changeClassname(length); } //光标键"↑" else if(event.keyCode==38){ this.index--; if(this.index<-1){ this.index=length - 1; }else if(this.index==-1){ this.obj.value=this.search_value; } this.changeClassname(length); } //回车键 else if(event.keyCode==13){ this.autoObj.className="auto_hidden"; this.index=-1; }else{ this.index=-1; } }, //程序入口 start: function(event){ if(event.keyCode!=13&&event.keyCode!=38&&event.keyCode!=40){ this.init(); this.deleteDIV(); this.search_value=this.obj.value; var valueArr=this.value_arr; valueArr.sort(); if(this.obj.value.replace(/(^\s*)|(\s*$)/g,'')==""){ return; }//值为空，退出 try{ var reg = new RegExp("(" + this.obj.value + ")","i");} catch (e){ return; } var div_index=0;//记录创建的DIV的索引 for(var i=0;i<valueArr.length;i++){ if(reg.test(valueArr[i])){ var div = document.createElement("div"); div.className="auto_onmouseout"; div.seq=valueArr[i]; div.οnclick=this.setValue(this); div.οnmοuseοver=this.autoOnmouseover(this,div_index); div.innerHTML=valueArr[i].replace(reg,"<strong>$1</strong>");//搜索到的字符粗体显示 this.autoObj.appendChild(div); this.autoObj.className="auto_show"; div_index++; } } } this.pressKey(event); window.οnresize=Bind(this,function(){this.init();}); }}//--></script><body> <div align="center" style="padding-top:50px"> <input type="text" style="width:300px;height:20px;font-size:14pt;" placeholder="请输入a或b模拟效果" id="o" οnkeyup="autoComplete.start(event)"> </div> <div class="auto_hidden" id="auto"><!--自动完成 DIV--></div><script> var autoComplete=new AutoComplete('o','auto',['b0','b12','b22','b3','b4','b5','b6','b7','b8','b2','abd','ab','acd','accd','b1','cd','ccd','cbcv','cxf']);</script></body></html>由提供