asp有象VB的combo控件一样的可以手动修改内容的下拉框码？
asp有象VB的combo控件一样的可以手动修改内容的下拉框码？或者类似的对象

------解决方案--------------------
ComboBox.js

function getLeftPostion( theObj )
{
var pos = 0;
while ( theObj != null )
{
pos += theObj.offsetLeft;
//get the Object which contain theObj.
theObj = theObj.offsetParent;
}
return pos;
}
function getTopPostion( theObj )
{
var pos = 0;
while ( theObj != null )
{
pos += theObj.offsetTop;
//get the Object which contain theObj.
theObj = theObj.offsetParent;
}
return pos;
}
function checkVersion()
{
var isBadVersion=true;
var curVer=navigator.appVersion;
var pos=parseInt(curVer.indexOf( "MSIE "));
if (pos> =1)
{
var intVer=parseInt(curVer.charAt(pos+5));
if (intVer> =5)
{ isBadVersion=false;}
}
if (isBadVersion)
{
var msg= "This page may not be displayed properly:\n "+
" This product requires Microsoft Internet Explorer 5 or later browser only. ";
alert(msg);
}
}

//check the browser version
checkVersion();

// the array of comboBoies
theArray = new Array();

function combobox(objId, objHandler)
{
this.comObj = document.all[objId];
this.comObj.selectedIndex = -1;
this.getValue = getValue;
this.doResize = doResize;
this.doChange = doChange;
this.loseFocus = loseFocus;
this.doSelectIdx = doSelectIdx;
this.focus = focus;

var strMsg= " ";

//------------------------------------------------------------------
// create the text object
//------------------------------------------------------------------
var txtObjIdName = objId + "_text ";

if (document.all[txtObjIdName] != null)
{
strMsg= "The following id: ' " + txtObjIdName + " ' is used internally by the Combo Box!\r\n "+
"Use of this id in your page may cause malfunction. Please use another id for your controls. ";
alert(strMsg);
}

var txtInner = " <INPUT type= 'text ' id= " + txtObjIdName + " name= " + txtObjIdName +
" onblur= ' " + objHandler + ".loseFocus() ' " +
" style= 'display: none; position: absolute ' value= ' ' > ";

this.comObj.insertAdjacentHTML( "afterEnd ", txtInner);

this.txtObj = document.all[txtObjIdName];
//------------------------------------------------------------------
// end
//------------------------------------------------------------------

this.beResizing = false;
this.doResize();
theArray[theArray.length] = this;
}

function loseFocus()
{
var theComObj = this.comObj;
var theTxtObj = this.txtObj;
var i;
theComObj.selectedIndex = -1;

if (theTxtObj.value == " ")
{ return; }

var optLen = theComObj.options.length;
for (i=0; i <optLen; i++)
{
var comVal = theComObj.options[i].text;
var txtVal = theTxtObj.value;

if (comVal == txtVal)
{ theComObj.selectedIndex = i;
return;
}
}
}

function doResize()