NuGet Package Requirements

This tutorial targets MySQL 8.0. The required NuGet packages are:

MySql.EntityFrameworkCore
Microsoft.EntityFrameworkCore
Microsoft.EntityFrameworkCore.Relational

These packages are designed for .NET Core/.NET 5+ Windows Forms applications. Standard .NET Framework projects do not support these version 8.0 packages, and older package versions may have compatibility issues with MySQL 8.0. As long as the application runs succesfully, the setup is considered correct.

Creating the Database Context

Create a MyDbContext class that inherits from DbContext. This class handles the database connection and serves as the entry point for Entity Framework operations.

using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace WinFormsApp1.MySql
{
    public class MyDbContext : DbContext
    {
        public DbSet<data1> tb_data1 { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            string connectionString = @"Server=localhost; Port=3306; Database=testdb; User=root; Password=yourpassword;";
            optionsBuilder.UseMySQL(connectionString);
        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);

            // Exclude specific fields from database mapping without removing from the model
            // modelBuilder.Entity<EntityName>().Ignore(x => x.PropertyName);
            //
            // Example: Exclude the text1 field from the data1 table
            // modelBuilder.Entity<data1>().Ignore(x => x.text1);

            // For tables without primary keys, use the following approach
            // modelBuilder.Entity<EntityName>().HasNoKey();
        }
    }
}

Key Configuration Methods

OnConfiguring

This method recieves the connection string and configures the database provider. The UseMySQL() method establishes the connection to the MySQL server using the specified parameters including host, port, database name, and credentials.

OnModelCreating

This method handles entity configuration at the model level. Common operations include:

• Ignoring properties: Use Ignore() to exclude specific model properties from database mapping
• Configuring keys: Use HasKey() to specify primary key properties
• Handling keyless entities: Use HasNoKey() for tables without defined primary keys

Usage Example

With the context configured, you can perform database operations within your WinForms application:

public partial class Form1 : Form
{
    private readonly MyDbContext _context;

    public Form1()
    {
        InitializeComponent();
        _context = new MyDbContext();
    }

    private void LoadData_Click(object sender, EventArgs e)
    {
        var records = _context.tb_data1.ToList();
        dataGridView1.DataSource = records;
    }
}

Always dispose of the context properly, preferably using a using statement or implementing IDisposable pattern to ensure database connections are closed appropriately.