10行代码，用1行搞定，好用！

LibDataTable roomdt = roomDataTable as LibDataTable;
if (!roomdt.Rows.Cast<DataRow>().Any(dRow => DataUtils.CStr(dRow["RoomId"]).Equals(roomId)))
{
WebApiResult = null;
return this.GetWebApiResultWrapper();
}
//bool isExist = false;
//foreach (DataRow row in roomdt.Rows)
//{
// if (row["RoomId"].ToString().Equals(roomId))
// {
// isExist = true;
// break;
// }
//}
//if (!isExist)
//{
// WebApiResult = null;
// return this.GetWebApiResultWrapper();
//}