DataManger?

 public class DataManager
    {
        string connectionString = “Data Source=(local);Initial Catalog=CompanyDb;Persist Security Info=True;User ID=sa;Password=123”;
        public int SqlExecuteQuery(string strQuery, int timeOut)
        {
            int returnCount = 0;
            SqlConnection sqlConnection = new SqlConnection();
            SqlCommand sqlCommand = new SqlCommand();
            SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(sqlCommand);
            sqlConnection.ConnectionString = connectionString;
            sqlConnection.Open();
            sqlCommand.CommandText = strQuery;
            sqlCommand.CommandTimeout = timeOut;
            sqlCommand.Connection = sqlConnection;
            returnCount = sqlCommand.ExecuteNonQuery();
            sqlConnection.Close();
            return returnCount;
        }

        public DataSet SqlSelectQuery(string strQuery, int timeOut)
        {
            DataSet ds = new DataSet();
            SqlConnection sqlConnection = new SqlConnection();
            SqlCommand sqlCommand = new SqlCommand();
            SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(sqlCommand);
            sqlConnection.ConnectionString = connectionString;
            sqlConnection.Open();
            sqlCommand.CommandText = strQuery;
            sqlCommand.CommandTimeout = timeOut;
            sqlCommand.Connection = sqlConnection;
            sqlDataAdapter.Fill(ds);
            sqlConnection.Close();
            return ds;
        }

        public object SqlScalarQuery(string strQuery, int timeOut)
        {
            object returnString = new object();
            SqlConnection sqlConnection = new SqlConnection();
            SqlCommand sqlCommand = new SqlCommand();
            SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(sqlCommand);
            sqlConnection.ConnectionString = connectionString;
            sqlConnection.Open();
            sqlCommand.CommandText = strQuery;
            sqlCommand.CommandTimeout = timeOut;
            sqlCommand.Connection = sqlConnection;
            returnString = sqlCommand.ExecuteScalar();
            sqlConnection.Close();
            return returnString;
        }
    }
———————————————————————————————————-
To generate Max Id

   public void GetStudentId()
        {
            string str = “select isnull(max(id),0)+1 from student”;
            TextBox6.Text = Convert.ToString(dm.SqlScalarQuery(str, 1000));
        }
———————————————————————————————————–