ขอถามเรื่อง Delegate + Event in C# ผมต้องเขียนโค้ดส่งค่าจากForm2 หา textBox1 ที่Form1 โดยต้องใช้ Delegate + Event

//Form1
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace TestDelegates1
{
    public delegate void MyDelegate(string msg);
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            new Form2(this).Show();
        }
        public void ShowMsg(string msg)
        {
            textBox1.Text = msg;
        }
    }
}


///Form2
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace TestDelegates1
{
    public partial class Form2 : Form
    {
        private Form1 frm1;
        public Form2(Form1 f)
        {
            InitializeComponent();
            frm1 = f;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            MyDelegate dg = new MyDelegate(frm1.ShowMsg);
            dg("Hello");
        }
    }
}

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            Form2 f2 = new Form2();
            f2.OnShowMsg += new Form2.MyDelegate(f2_OnShowMsg);
            f2.Show();
        }

        void f2_OnShowMsg(string msg)
        {
            MessageBox.Show(msg);
        }
    }

public partial class Form2 : Form
    {
        public delegate void MyDelegate(string msg);
        public event MyDelegate OnShowMsg;

        public Form2()
        {
            InitializeComponent();
            Load += new EventHandler(Form2_Load);
       }

        void Form2_Load(object sender, EventArgs e)
        {
            OnShowMsg("Form2_Load");
        }
    }