Pessimistic locking is not supported by the data providers because connection is always open so we use datasets for this purpose.

You can achieve this with the help of transactions by providing proper isolation.

Pessimistic approach follows the way of isolation for providing concurrency, so that is why we provide isolation at the application and the database level.

 void TestPessimisticConcurrency()
        {
            try
            {
                //Create a connection object
                string ConnectionString = "Integrated security = SSPI;" +
                "Initial Catalog = Northwind;" + "Data Source = localhost;";
                SqlConnection conn = new SqlConnection(ConnectionString);
                conn.Open();

                // Create a transaction that locks the records of the query
                SqlTransaction tr = conn.BeginTransaction
                (IsolationLevel.RepeatableRead, "test");

                //Create a command that updates the order of
                //the database using the transaction
                SqlCommand cmd = new SqlCommand("UPDATE Orders SET " +
                "ShippedDate = '5/10/01', ShipCity = 'Columbus' WHERE" +
                "OrderID = 10248", conn, tr);

                // Execute the update
                cmd.ExecuteNonQuery();

                // Generate Message
                MessageBox.Show("Wait for KeyPress.");
                tr.Commit(); // Transaction is committed
                conn.Close();
            }

            catch (SqlException ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
        }