于是这code便诞生了，如下：
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>无标题页</title>
<script type="text/javascript" language="javascript">
var currentIndex=-1;//保存提示框中选择的索引
var sumSearchCount=0;//保存提示框中数据数量
var tempValue="";//保存当前输入的要搜索的内容
var objTxt="";//保存文本框对象
var top=0;//提示框的top
var left=0;//提示框的left
var width=0;//提示框的width
var values = new Array();//保存下拉列表的值
var texts = new Array();//保存下拉列表的显示内容
var tempDiv=new Array();//保存提示框中索引对应的values索引
//获取下拉列表的值和显示内容
function getSelectValues(ddl){
ddlvalue = document.getElementById("DropDownList1");
for(var i=0;i<ddlvalue.length;i++){
values[i]=ddlvalue.options[i].value;
texts[i]=ddlvalue.options[i].text;
}
}
var oInterval = "";//保存自动计时对象
function fnStartInterval(txt_id){
getSelectValues("DropDownList1");
objTxt=txt_id;//获取输入文本框对象
top = getLength("offsetTop")+objTxt.offsetHeight;
left= getLength("offsetLeft");
width=objTxt.offsetWidth;
oInterval = window.setInterval("beginSearch()",2000);//启用计时
}
//获取对应属性的长度
function getLength(attribute)
{
var offset = 0;
var txt_input = document.getElementById("txtSearch");
while (item)
{
offset += txt_input[attribute];
txt_input = txt_input.offsetParent;
}
return offset;
}
//停止计时
function fnStopInterval()
{
window.clearInterval(oInterval);
}
//自动完成提示
function beginSearch(){
if(objTxt.value.length>0 && tempValue!=objTxt.value)
{
sumSearchCount=0;
tempValue=objTxt.value;
var div_show = document.getElementById("divMsg");
div_show.style.top=top+"px";
div_show.style.display="block";
div_show.style.left=left+"px";
div_show.style.width=width+"px";
div_show.innerHTML="";
var leng = texts.length;
var txt_value = objTxt.value;
var row="";
for(var i=0;i<leng;i++){
if(texts[i].indexOf(txt_value)!=-1){
row = row + "<div style=\"font-size:14px; display:block; width:100%\" id='divsearch_"+i+"' onmouseover=\"this.style.backgroundColor='#3366CC';currentIndex="+i+";\" onmouseout=\"this.style.backgroundColor='';currentIndex=-1;\" onclick=\"span_click(this)\" >"+texts[i]+"</div>";
tempDiv[sumSearchCount]=i;
sumSearchCount++;
}
}
div_show.innerHTML=row;
}
else if(objTxt.value.length==0 || objTxt.value == null)
{
var div_msg = document.getElementById("divMsg");
div_msg.style.display="none";
div_msg.innerHTML="";
}
}
//提示内容单击保存到文本框中
function span_click(sp)
{
clear();
objTxt.value=sp.innerHTML;
document.getElementById("DropDownList1").options[sp.id.substring(sp.id.indexOf('_')+1,sp.id.length)].selected="selected";
}
//停止查询，关闭提示
function closeSearch()
{
var tbl = document.activeElement.parentElement;
if(tbl && tbl.id!="divMsg")//防止使用上下键后丢失提示内容
{
clear();
document.getElementById("divMsg").innerHTML="";
}
else if(currentIndex==-1)
{
clear();
document.getElementById("divMsg").innerHTML="";
}
}
//清空提示
function clear()
{
fnStopInterval();
currentIndex=-1;
tempValue="";
document.getElementById("divMsg").style.display="none";
}
//使用键盘上下方向键和enter键
function changeSelect()
{
var divContent = document.getElementById("divMsg");
if(divContent && divContent.style.display=="block")
{
if (event.keyCode == 38 || event.keyCode == 40 || event.keyCode == 13)
{
if(currentIndex!=-1) document.getElementById("divsearch_"+tempDiv[currentIndex]).style.backgroundColor="";
if (event.keyCode == 38 && currentIndex > 0)
{
currentIndex--;
document.getElementById("divsearch_"+tempDiv[currentIndex]).style.backgroundColor="#3366CC";
}
else if (event.keyCode == 40 && currentIndex < sumSearchCount-1)
{
currentIndex++;
document.getElementById("divsearch_"+tempDiv[currentIndex]).style.backgroundColor="#3366CC";
}
else if (event.keyCode == 13)
{
if(currentIndex > -1)
{
var divpart = document.getElementById("divsearch_"+tempDiv[currentIndex]);
objTxt.value=divpart.innerHTML;
document.getElementById("DropDownList1").options[tempDiv[currentIndex]].selected="selected";
clear();
}
}
}
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<input type="text" id="txtSearch" autocomplete="off" onkeydown="changeSelect()" onfocus="fnStartInterval(this)" onblur="closeSearch()" runat="server" />
<asp:DropDownList ID="DropDownList1" runat="server" DataTextField="slr_realname" DataValueField="systemloginrecord_id" DataSourceID="ObjectDataSource1" Width="130px">
</asp:DropDownList><asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="GetRecordDS"
TypeName="TestDAL"></asp:ObjectDataSource>
</div>
<div style="display:none; z-index:2; text-align:left; position:absolute; border:solid 1px;" id="divMsg">
</div>
</form>
</body>
</html>
<input type="text" id="txtSearch" autocomplete="off"。。。这里加入了autocomplete属性，屏蔽了文本框输入记录提示功能，虽然这个功能很好，但是在这里却成了绊脚石。呵呵
以前没有写博客的习惯，好多不经常使用的东西用过就忘了。以后是要整理整理了。