i treid my level best but capturing copy from screen

Question

 

i tried my level best  but capturing copy from screen not be able to get the full height.

 

 My Code as follows

 

protected void btnCaptures_Click(object sender, EventArgs e)
{

Bitmap bitmap = new Bitmap

(System.Windows.Forms.Screen.PrimaryScreen.Bounds.Width, System.Windows.Forms.Screen.PrimaryScreen.Bounds.Height);

Graphics graphics = Graphics.FromImage(bitmap as System.Drawing.Image);

graphics.CopyFromScreen(0, 0, 0, 0, bitmap.Size);

bitmap.Save(Server.MapPath(@"Screen\ScreenShot2.Bmp"), ImageFormat.Bmp);

}

I tried my above serveral times, but when i run the above code in Screen folder copy fromscreen full height i cannot able to get.

for that getting a full height from copyfromscreen what changes i want to go in above code. 

 

please help me i tried my above with 3 to 4 days not able to get the excepted output.

 

Regards,

Narasiman P.