how to give a focus to process

using System;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Diagnostics;

namespace WindowsApplication1 {
  public partial class Form1 : Form {
    public Form1() {
      InitializeComponent();
    }
    [System.Runtime.InteropServices.DllImport("user32.dll")]
    private static extern bool SetForegroundWindow(IntPtr hWnd);

    private void button1_Click(object sender, EventArgs e) {
      Process[] procs = Process.GetProcessesByName("notepad"); //app name here
      if (procs.Length > 0) {
        // Which one?  I'll just pick the first
        if (procs[0].MainWindowHandle != IntPtr.Zero)
          SetForegroundWindow(procs[0].MainWindowHandle);
      }
    }
  }
}