Arcengine获得模型（工具）是否存在

 public static bool Exists(IGeoProcessor gp, string modalname)
        {
            IGpEnumList pList = gp.ListTools("");
            string name = pList.Next();

            while (name != "")
            {

                if (modalname == name) return true;
                name = pList.Next();

            }
            return false;
        }