C#

public const int WM_PASTE = 0x0302;

[DllImport("User32.dll")]
public static extern Int32 FindWindow(String lpClassName,String lpWindowName);

[DllImport("user32.dll", CharSet=CharSet.Auto)]
public static extern int SendMessage(int hWnd, int msg, int wParam, IntPtr lParam);

private void btn_Click(object sender, System.EventArgs e)
{
	int hwnd=0;
	hwnd = FindWindow(null, "Untitled - Notepad");

	if (hwnd != 0)
	{
		Clipboard.SetText("sample text from clipboard");
		hwnd = FindWindow(null, "Untitled - Notepad");
		SendMessage(hwnd, WM_PASTE, 0, IntPtr.Zero);
	}
}

SendMessage, WM_PASTE<br />
SendMessage, WM_CHAR<br />
PostMessage, WM_PASTE<br />
PostMessage, WM_CHAR

SendMessage, (WM_KEYDOWN, WM_KEYUP) For CTRL+V<br />
PostMessage, (WM_KEYDOWN, WM_KEYUP) For CTRL+V

<br />
public class Complex<br />
    {<br />
        public int a, b, c;<br />
<br />
        public override bool Equals(object obj)<br />
        {<br />
            if (obj is Complex)<br />
            {<br />
                Complex other = (Complex)obj;<br />
                if (other.a == this.a <br />
                    && other.b == this.b <br />
                    && other.c == this.c)<br />
                {<br />
                    return true;<br />
                }<br />
            } <br />
<br />
            return false;<br />
        }<br />
<br />
        public override int GetHashCode()<br />
        {<br />
            return a.GetHashCode() ^ b.GetHashCode(); // Purpose to omit "c" is to test behavior if Equals and GetHashCode compute differently<br />
        }<br />
    }<br />
...<br />
Complex c1 = new Complex();<br />
                c1.a = 1;<br />
                c1.b = 2;<br />
                c1.c = 3;<br />
                Complex c2 = new Complex();<br />
                c2.a = 1;<br />
                c2.b = 2;<br />
                c2.c = 5;<br />
<br />
                System.Collections.Hashtable SomeDict = new System.Collections.Hashtable();<br />
                SomeDict.Add(c1, DateTime.Now);<br />
                SomeDict.Add(c2, DateTime.Now);<br />