在书上摘抄的一个调用示例方法   

<?xml version="1.0" encoding="utf-8"?>
<mx:Application    xmlns:mx="http://www.adobe.com/2006/mxml" >
<mx:HTTPService id="myhttp" url="http://www.diabolab.com/books/flex3/samplePost.php"
method="post" showBusyCursor="true" >
<mx:request xmlns="">
<a>   {tiA.text}  </a>
<b>{tiB.text}</b>
</mx:request>
</mx:HTTPService>
<mx:Panel title="使用Httpservice"
paddingLeft="3" paddingRight="3" paddingBottom="3" paddingTop="3">
<mx:HBox>
<mx:TextInput id="tiA" width="50" text="1"/>
<mx:Label text="+"/>
<mx:TextInput id="tiB" width="50" text="1"/>
<mx:Label text="="/>
<mx:TextInput id="tiC" width="50" text="{myhttp.lastResult}" editable="false"/>
</mx:HBox>
<mx:Button id="btnPost" label="提交" click="{myhttp.send()}"/>
</mx:Panel>
</mx:Application>