Set Window Action - (Minimize / Maximize)

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Diagnostics;

namespace WindowAction
{
    public partial class NotepadMinimize : Form
    {
        [DllImport("user32.dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        static extern bool GetWindowPlacement(IntPtr hWnd, ref WINDOWPLACEMENT lpwndpl);
        [DllImport("user32.dll", SetLastError = true)]
        static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
        [DllImport("user32.dll")]
        static extern bool SetWindowPlacement(IntPtr hWnd, ref WINDOWPLACEMENT lpwndpl);

        private struct POINTAPI
        {
            public int x;
            public int y;
        }

        private struct RECT
        {
            public int left;
            public int top;
            public int right;
            public int bottom;
        }

        private struct WINDOWPLACEMENT
        {
            public int length;
            public int flags;
            public int showCmd;
            public POINTAPI ptMinPosition;
            public POINTAPI ptMaxPosition;
            public RECT rcNormalPosition;
        }


        public NotepadMinimize()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            WindowAction_MinimizeNotepad();
        }

        void WindowAction_MinimizeNotepad()
        {
            System.IntPtr app_hwnd;
            WINDOWPLACEMENT wp = new WINDOWPLACEMENT();
            app_hwnd = FindWindow("Notepad", null);
            GetWindowPlacement(app_hwnd, ref wp);
            wp.showCmd = 2;
            SetWindowPlacement(app_hwnd, ref wp);
        }

        private void minWindow()
        {
            Process[] processes = Process.GetProcessesByName(textBox1.Text.Trim());
            foreach (Process p in processes)
            {
                System.IntPtr app_hwnd;
                WINDOWPLACEMENT wp = new WINDOWPLACEMENT();
                app_hwnd = p.MainWindowHandle;
                GetWindowPlacement(app_hwnd, ref wp);
                wp.showCmd = 2; // 1- Normal; 2- Minimize; 3-Maximize;
                SetWindowPlacement(app_hwnd, ref wp);
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            minWindow();
        }

    }
}