asp有象VB的combo控件一样的可以手动修改内容的下拉框码？

this.txtObj.style.posLeft = getLeftPostion(this.comObj);

this.txtObj.style.posTop = getTopPostion(this.comObj) + 1;

this.txtObj.style.posWidth = this.comObj.offsetWidth - 16;

this.txtObj.style.posHeight = this.comObj.offsetHeight;

this.comObj.style.position ="absolute";

this.comObj.style.posLeft = this.txtObj.style.posLeft;

this.comObj.style.posTop = this.txtObj.style.posTop;

this.offWidth = this.comObj.offsetWidth;

var strRect = "rect(0 "+(this.comObj.offsetWidth)+" "+ this.comObj.offsetHeight +

" "+(this.txtObj.style.posWidth - 2 )+")";

this.comObj.style.clip = strRect;

this.txtObj.style.display="";

this.beResizing = false;

}

}

function doChange()

{

var idx = this.comObj.selectedIndex;

var opt = this.comObj.options[idx];

this.txtObj.value = opt.text;