2、可用方向键选择。
3、如果选择的当前元素为首元素，则按上（方向键）则会自动跳到末元素。
4、如果选择的当前元素为末元素，则按下（方向键）则会自动跳到首元素。
5、当获取值为空时，自动隐藏 自动完成TIP的容器
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"><HTML><HEAD><TITLE> New Document </TITLE><META NAME="Generator" CONTENT="EditPlus"><META NAME="Author" CONTENT=""><META NAME="Keywords" CONTENT=""><META NAME="Description" CONTENT=""><style>
body,div {
body,div 
font-family:verdana;line-height:100%;font-size:9pt;
}input {300px;}h1 {text-align:center;font-size:2.2em;}#divf {margin:10px;font-size:0.8em;text-align:center;}#divc {border:1px solid #333333;}.des {500px;background-color:lightyellow;border:1px solid #333;padding:20px;margin-top:20px;}.mouseover {color:#ffffff;background-color:highlight;100%;cursor:default;}.mouseout {color:#000000;100%;background-color:#ffffff;cursor:default;}</style><SCRIPT LANGUAGE="JavaScript"><!--// script by blueDestiny// Email : blueDestiny [at] 126 . com// Object: jsAuto// browser: ie, mf.// example:// step1 : // create autocomplete container, return object and bind event to the object, and ///create a new jsAuto instance:// <div id="divautocomplete"></div>// var autocomplete = new jsAuto("autocomplete","divautocomplete")// handle event:// autocomplete.handleEvent(value, returnObjectID)// <input id="rautocomplete" onkeyup="autocomplete.handleEvent(this.value,"ratocomplete",event)>// step2 :// add autocompete item:// autocomplete.item(string)// string must be a string var, you can split the string by ","// autocomplete.item("blueDestiny,never-online,csdn,blueidea")// http://www.never-online.com//instanceName为你生成的实例名，objID为监听的对象ID//具体请见最下面的例子function jsAuto(instanceName,objID){ //初始化成员； //_msg: 预先实例化的自动完成内容 this._msg = []; this._x = null; this._o = document.getElementById( objID ); if (!this._o) return; //标志flag的缩写 this._f = null; //instanceName的缩写 this._i = instanceName; //返回的对象 //returnObject this._r = null; //按上下键时，得到当前的mouseover是第几个元素 //count this._c = 0; //是否可以执行按上下键 //selectflag this._s = false; //Value的缩写 this._v = null; //初始化object的状态 this._o.style.display = "none"; this._o.style.position = "absolute"; this._o.style.zIndex = "9999"; this._offset=function(e)
{
var t = e.offsetTop; var l = e.offsetLeft; var w = e.offsetWidth; var h = e.offsetHeight; while(e=e.offsetParent) { t+=e.offsetTop; l+=e.offsetLeft;
} return { t : t, l : l, w : w, h : h } } return this;};//触发的按上下的键盘事件//效率不算高，可优化jsAuto.prototype.directionKey=function() { with (this){ var e = _e.keyCode ? _e.keyCode : _e.which; var l = _o.childNodes.length; (_c>l-1 || _c<0) ? _s=false : ""; if( e==40 && _s ) { _o.childNodes[_c].className="mouseout"; (_c >= l-1) ? _c=0 : _c ++; _o.childNodes[_c].className="mouseover"; } if( e==38 && _s ) { _o.childNodes[_c].className="mouseout"; _c--<=0 ? _c = _o.childNodes.length-1 : ""; _o.childNodes[_c].className="mouseover"; } if( e==13 ) { if(_o.childNodes[_c] && _o.style.display=="block") { _r.value = _x[_c]; _o.style.display = "none"; } } if( !_s ) { _c = 0; _o.childNodes[_c].className="mouseover"; _s = true; }}};// mouseEvent.// 鼠标事件jsAuto.prototype.domouseover=function(obj) { with (this){ _o.childNodes[_c].className = "mouseout"; _c = 0; obj.tagName=="DIV" ? obj.className="mouseover" : obj.parentElement.className="mouseover";}};jsAuto.prototype.domouseout=function(obj){ obj.tagName=="DIV" ? obj.className="mouseout" : obj.parentElement.className="mouseout";};jsAuto.prototype.doclick=function(msg) { with (this){ if(_r) { _r.value = msg; _o.style.display = "none"; } else { alert("javascript autocomplete ERROR :\n\n can not get return object."); return; }}};// object method;// 对象的原型方法// 添加项目;// 可以用英文,分割// JK说的是对的，我当初也是不想用逗号的// 如果你不想用,分割，可自己改写这里jsAuto.prototype.item=function(msg){ if( msg.indexOf(",")>0 ) { var arrMsg=msg.split(","); for(var i=0; i<arrMsg.length; i++) { arrMsg[i] ? this._msg.push(arrMsg[i]) : ""; } } else { this._msg.push(msg); } this._msg.sort();};jsAuto.prototype.append=function(msg) { with (this){ _i ? "" : _i = eval(_i); _x.push(msg); var div = document.createElement("DIV"); //bind event to object. div.onmouseover = function(){_i.domouseover(this)}; div.onmouseout = function(){_i.domouseout(this)}; div.onclick = function(){_i.doclick(msg)}; var re = new RegExp("(" + _v + ")","i"); div.style.lineHeight="140%"; div.className = "mouseout"; if (_v) div.innerHTML = msg.replace(re , "<strong>$1</strong>"); div.style.fontFamily = "verdana"; _o.appendChild(div);}};jsAuto.prototype.display=function() { with(this){ if(_f&&_v!="") { var l = _offset(_r); _o.style.left = l.l; _o.style.width = l.w; _o.style.top = l.t + l.h; _o.style.display = "block"; _o.style.display = "block"; } else { _o.style.display="none"; }}};jsAuto.prototype.handleEvent=function(fValue,fID,event) { with (this){ var re; _e = event; var e = _e.keyCode ? _e.keyCode : _e.which; _x = []; _f = false; _r = document.getElementById( fID ); _v = fValue; // 这里用eval，返回生成的实例对象。 _i = eval(_i); re = new RegExp("^" + fValue + "", "i"); _o.innerHTML=""; for(var i=0; i<_msg.length; i++) { if(re.test(_msg[i])) { _i.append(_msg[i]); _f = true; } } _i ? _i.display() : alert("can not get instance"); if(_f) { // 触发上下键盘的事件 if((e==38 || e==40 || e==13)) { _i.directionKey(); } else { _c=0; _o.childNodes[_c].className = "mouseover"; _s=true; } }}};window.onerror=new Function("return true;");//--></SCRIPT></HEAD><BODY><div id="divc"><!--this is the autocomplete container.--></div><h1>Autocomplete Function</h1><div align="center"><input onkeyup="jsAutoInstance.handleEvent(this.value,'auto',event)" id="auto"></div><div id="divf">Power By Miracle, never-online</div><SCRIPT LANGUAGE="JavaScript"><!--var jsAutoInstance = new jsAuto("jsAutoInstance","divc");jsAutoInstance.item("a-start,b-start,c-start,d-start,e-start,f-start,g-start,h-start,i-start,j-start,k-start,l-start,m-start,n-start,o-start,p-start,q-start,r-start,s-start,t-start,u-start,v-start,w-start,x-start,y-start,z-start,z-start");jsAutoInstance.item("blueDestiny");jsAutoInstance.item("BlueMiracle,Blue");jsAutoInstance.item("angela,geniuslau");jsAutoInstance.item("never-online");//--></SCRIPT></BODY></HTML></body></html>