GetComponentを上位の階層に対して。SendMessageUpwardsのかわりに。

gistfile1.cs

public static T GetComponentUpward<T>(GameObject gObj) where T: Component
{
	T comp = gObj.GetComponent<T>();
	if(comp != null){
		return comp;
	}else{
		Transform parentTrans = gObj.transform.parent;
		if( parentTrans != null){
			return GetComponentUpward<T>(parentTrans.gameObject);
		}else{
			return null;
		}
	}
}