dbtest.cs

using System;
using System.Windows.Forms;
using MySql.Data.MySqlClient;

namespace CRUDWindowsFormsApp
{
    public partial class MainForm : Form
    {
        private string connectionString = "Server=myServerAddress;Database=myDatabase;User Id=myUsername;Password=myPassword;";

        public MainForm()
        {
            InitializeComponent();
        }

        private void MainForm_Load(object sender, EventArgs e)
        {
            LoadData();
        }

        private void LoadData()
        {
            using (MySqlConnection connection = new MySqlConnection(connectionString))
            {
                connection.Open();

                string selectQuery = "SELECT * FROM TableName";
                using (MySqlCommand cmd = new MySqlCommand(selectQuery, connection))
                {
                    using (MySqlDataReader reader = cmd.ExecuteReader())
                    {
                        dataGridView.DataSource = null;
                        dataGridView.Rows.Clear();

                        while (reader.Read())
                        {
                            dataGridView.Rows.Add(reader["ID"], reader["Name"], reader["Age"]);
                        }
                    }
                }
            }
        }

        private void btnCreate_Click(object sender, EventArgs e)
        {
            string name = txtName.Text;
            int age;

            if (int.TryParse(txtAge.Text, out age))
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    connection.Open();

                    string insertQuery = "INSERT INTO TableName (Name, Age) VALUES (@Name, @Age)";
                    using (MySqlCommand cmd = new MySqlCommand(insertQuery, connection))
                    {
                        cmd.Parameters.AddWithValue("@Name", name);
                        cmd.Parameters.AddWithValue("@Age", age);
                        cmd.ExecuteNonQuery();

                        MessageBox.Show("Record created successfully!");
                        LoadData();
                    }
                }
            }
            else
            {
                MessageBox.Show("Please enter a valid age.");
            }
        }

        private void btnUpdate_Click(object sender, EventArgs e)
        {
            int id;
            if (int.TryParse(txtID.Text, out id))
            {
                string name = txtName.Text;
                int age;

                if (int.TryParse(txtAge.Text, out age))
                {
                    using (MySqlConnection connection = new MySqlConnection(connectionString))
                    {
                        connection.Open();

                        string updateQuery = "UPDATE TableName SET Name = @Name, Age = @Age WHERE ID = @ID";
                        using (MySqlCommand cmd = new MySqlCommand(updateQuery, connection))
                        {
                            cmd.Parameters.AddWithValue("@Name", name);
                            cmd.Parameters.AddWithValue("@Age", age);
                            cmd.Parameters.AddWithValue("@ID", id);
                            cmd.ExecuteNonQuery();

                            MessageBox.Show("Record updated successfully!");
                            LoadData();
                        }
                    }
                }
                else
                {
                    MessageBox.Show("Please enter a valid age.");
                }
            }
            else
            {
                MessageBox.Show("Please enter a valid ID.");
            }
        }

        private void btnDelete_Click(object sender, EventArgs e)
        {
            int id;
            if (int.TryParse(txtID.Text, out id))
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    connection.Open();

                    string deleteQuery = "DELETE FROM TableName WHERE ID = @ID";
                    using (MySqlCommand cmd = new MySqlCommand(deleteQuery, connection))
                    {
                        cmd.Parameters.AddWithValue("@ID", id);
                        cmd.ExecuteNonQuery();

                        MessageBox.Show("Record deleted successfully!");
                        LoadData();
                    }
                }
            }
            else
            {
                MessageBox.Show("Please enter a valid ID.");
            }
        }
    }
}