In this article I will explain with an example, how to update data into MySQL database in Windows Forms (WinForms) Application with C# and VB.Net.
 
 

Database

I have made use of the following table Customers with the schema as follows.
Update into MySQL Database in C# and VB.Net
 
I have already inserted few records in the table.
Update into MySQL Database in C# and VB.Net
 
Note: You can download the database table SQL by clicking the download link below.
          Download SQL file
 
 

Form Design

The Form consists of following controls:
Label – For labeling the controls.
TextBox – For capturing the values of CustomerId, Name and Country.
Button – For updating record.
The Button has been assigned with a Click event handler.
Update into MySQL Database in C# and VB.Net
 
 

Namespaces

You will need to import the following namespaces.
C#
using System.Configuration;
using MySql.Data.MySqlClient;
 
VB.Net
Imports System.Configuration
Imports MySql.Data.MySqlClient
 
 

Updating the record into MySQL Database in C# and VB.Net

When Update button is clicked, first the connection is read from App.Config file.
Note: For more details on how to read connection string from App.Config file, please refer my article .Net 4.5: Read (Get) Connection String from App.Config file using C# and VB.Net.
 
The values of CustomerId, Name and Country fields are fetched from their respective TextBoxes and the record is updated into MySQL database using ExecuteNonQuery method of MySqlCommand class.
Note: For more details on ExecuteNonQuery method, please refer my article Understanding MySqlCommand ExecuteNonQuery in C# and VB.Net.
 
Finally, based on whether record is updated or not, an appropriate message is displayed using MessageBox class.
C#
private void OnUpdate(object sender, EventArgs e)
{
    string sql = "UPDATE Customers SET Name=@Name, Country=@Country WHERE CustomerId=@CustomerId";
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (MySqlConnection con = new MySqlConnection(constr))
    {
       using (MySqlCommand cmd = new MySqlCommand(sql, con))
        {
            cmd.Parameters.AddWithValue("@CustomerId", txtId.Text);
            cmd.Parameters.AddWithValue("@Name", txtName.Text);
            cmd.Parameters.AddWithValue("@Country", txtCountry.Text);
            con.Open();
            int i = cmd.ExecuteNonQuery();
            con.Close();
 
            if (i > 0)
            {
                MessageBox.Show("Customer record updated.");
            }
            else
            {
                MessageBox.Show("Customer not found.");
            }
        }
    }
}
 
VB.Net
Private Sub OnUpdate(sender As Object, e As EventArgs) Handles btnUpdate.Click
    Dim sql As String = "UPDATE Customers SET Name=@Name, Country=@Country WHERE CustomerId=@CustomerId"
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As MySqlConnection = New MySqlConnection(constr)
        Using cmd As MySqlCommand = New MySqlCommand(sql, con)
            cmd.Parameters.AddWithValue("@CustomerId", txtId.Text)
            cmd.Parameters.AddWithValue("@Name", txtName.Text)
            cmd.Parameters.AddWithValue("@Country", txtCountry.Text)
            con.Open()
            Dim i As Integer = cmd.ExecuteNonQuery()
            con.Close()
            If i > 0 Then
                MessageBox.Show("Customer record updated.")
            Else
                MessageBox.Show("Customer not found.")
            End If
        End Using
    End Using
End Sub
 
 

Screenshot

Update into MySQL Database in C# and VB.Net
 
 

Downloads

Download Code