private void Save_Click(object sender, EventArgs e) { if (IdNumber.Text == "") { MessageBox.Show("Please Enter ID Number"); IdNumber.Select(); } else if (NameData.Text == "") { MessageBox.Show("Please Enter Name"); NameData.Select(); } else if (Amount.Text == "") { MessageBox.Show("Please Enter Amount"); Amount.Select(); } else if (Location.Text == "") { MessageBox.Show("Please Enter Location"); Location.Select(); } else { using (OleDbConnection connection = new OleDbConnection()) { try { connection.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=database/dataBase.mdb"; cmd.Connection = connection; // cmd.CommandText = "SELECT * FROM Product WHERE IdNumber = " + Form1.Idnumber; cmd.CommandText = "insert into Product ([IdNumber],[Name],[Amount],[Location]) values (@IdNumber,@Name,@Amount,@Location)"; cmd.Parameters.AddWithValue("@IdNumber", IdNumber.Text); cmd.Parameters.AddWithValue("@Name", NameData.Text); cmd.Parameters.AddWithValue("@Amount", int.Parse(Amount.Text)); cmd.Parameters.AddWithValue("@Location", Location.Text); if (connection.State != ConnectionState.Open) { connection.Open(); } cmd.ExecuteNonQuery(); connection.Close(); this.Close(); } catch (OverflowException ex) { MessageBox.Show("ID Number exceeded the maximum permissible length "); } catch (Exception ex) { MessageBox.Show("Error"); } } } }