Datagridview行重复

Question

每当我向datagridview添加一个新行时，我都会从当前添加的行中获取重复的行。我正在使用外部mysql数据库。

private void FillTable()
    {
        try
        {
            MySqlConnection DBConn = new MySqlConnection(MysqlConnectionString);
            MySqlCommand Command = new MySqlCommand("SELECT DISTINCT Voornaam, Achternaam, Leeftijd, GBDag, GBMaand, GBJaar, Adres, Woonplaats, Postcode FROM Libra_Klanten ORDER BY Voornaam", DBConn);
            MySqlDataAdapter Adapter = new MySqlDataAdapter(Command.CommandText, DBConn);
            MySqlCommandBuilder Builder = new MySqlCommandBuilder(Adapter);

            DBConn.Open();
            Command.ExecuteNonQuery();
            Adapter.Fill(CustomersTable);

            CustomersDataViewer.DataSource = CustomersTable;
            CustomersDataViewer.DataMember = CustomersTable.TableName;
            CustomersDataViewer.AutoResizeColumns();

            DBConn.Close();

            DBConn.Dispose();
            Command.Dispose();
            Adapter.Dispose();
            Builder.Dispose();
        }
        catch (Exception Ex)
        {
            Debug.WriteLine(Ex.Message);
        }
    }

这是insert语句的代码：

private void ButtonInsertCustomer_Click(object sender, EventArgs e)
    {
        if (TextBoxVoornaam.TextLength > 0 && TextBoxAchternaam.TextLength > 0 && NumLeeftijd.Value > 0 && DateGeboorteDatum.Value != null && TextBoxAdres.TextLength > 0 && TextBoxWoonplaats.TextLength > 0 && TextBoxPostcode.TextLength > 0)
        {
            try
            {
                MySqlConnection DBConn = new MySqlConnection(MysqlConnectionString);
                MySqlCommand Command = new MySqlCommand("INSERT INTO Libra_Klanten (Voornaam, Achternaam, Leeftijd, GBDag, GBMaand, GBJaar, Adres, Woonplaats, Postcode) values ('" + TextBoxVoornaam.Text + "','" + TextBoxAchternaam.Text + "','" + NumLeeftijd.Value + "','" + DateGeboorteDatum.Value.Day + "','" + DateGeboorteDatum.Value.Month + "','" + DateGeboorteDatum.Value.Year + "','" + TextBoxAdres.Text + "','" + TextBoxWoonplaats.Text + "','" + TextBoxPostcode.Text + "')", DBConn);

                DBConn.Open();
                Command.ExecuteNonQuery();
                DBConn.Close();

                DBConn.Dispose();
                Command.Dispose();
                FillTable();
            }
            catch (MySqlException ex)
            {
                Debug.WriteLine(ex.Message);
            }
        }
        else
        {
            MessageBox.Show("Vul alle velden in.");
        }
    }

每次我将新客户插入数据库时​​，都会显示我添加的前一行的副本。我已经尝试在datagridview上使用.Clear()，但这不起作用。

Answer 1

由于您的datagridview绑定到数据源，您需要清除数据源本身。

在CustomersTable.Clear();方法的开头运行FillTable，以确保您的数据源中没有数据; datagridview将反映这一点。