public int fGetExistUserName(string oldUserName, string newUserName) { int exist = 0; Data.OPEN_CONNECTION(Data.CONECTION); Data.CMD = new System.Data.SqlClient.SqlCommand("DECLARE @exist INT " + "if exists (select top 1 * from dbo.[CONFIG_USER] c where c.[UserName]= '" + newUserName + "' and c.[UserName] <> '" + oldUserName + "' )" + "SET @exist = 1 " + "ELSE " + "SET @exist = 0 " + "SELECT @exist AS EXIST", Data.CNN); Data.SQLDR = Data.CMD.ExecuteReader(); while (Data.SQLDR.Read()) { exist = int.Parse(Data.SQLDR[0].ToString()); } return(exist); }//fin de la funcion