Flex LinkButton鼠标划过出现下划线

在LinkButton中 textDecoration属性设置label的是否有下划线装饰，属性值分为"none","underline"

代码如下------>

<mx:LinkButton id="test" x="326" y="163" width="136" height="86" label="测试数据"
       click="test1_clickHandler(event)" fontSize="22"
       mouseOut="test.setStyle('textDecoration', 'none')"
       mouseOver="test.setStyle('textDecoration', 'underline')"   textDecoration="none"/>