var styleObj = new mx.styles.CSSStyleDeclaration;
styleObj.styleName = "newStyle";
_global.styles.newStyle = styleObj;
styleObj.fontFamily = "_sans";
styleObj.fontSize = 14;
styleObj.fontWeight = "bold";
styleObj.textDecoration = "underline";
styleObj.color = 0x336699;
styleObj.setStyle("themeColor", "haloBlue");
labelname.setStyle("styleName", "newStyle");
//希望你更好的利用flash的“帮助”
//其中labelname为你的label的name（废话。。。）
