ComboBox

<?xml version="1.0" encoding="utf-8"?> 
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" creationComplete="initCB();" width="283" height="102"> 
 <mx:Style> 
  global{ 
   fontSize: 12px 
  } 
 </mx:Style> 
 <mx:Script> 
  <![CDATA[ 
   private function initCB():void{ 
    var info:Array = new Array(); 
    info.push({label:"B1", data:"3"}); 
    info.push({label:"B2", data:"2"}); 
    this.cb1.dataProvider = info; 
   } 

   private function setCB1Index():void{   //根据值查询数据，如：数据来自库文件 
    for each(var obj:Object in cb1.dataProvider){ 
     if(obj.data==edit_txt.text){ 
      cb1.selectedItem=obj; 
      break; 
     } 
    } 
//    cb1.selectedIndex=0;      //数据固定，已经知道序号 
   } 
  ]]> 
 </mx:Script>    
 <mx:ComboBox x="25.5" y="24" id="cb1"></mx:ComboBox> 
 <mx:TextInput x="25.5" y="56" id="edit_txt"/> 
 <mx:Button x="193.5" y="55" label="Click" click="setCB1Index();"/> 
</mx:Application>