draw vertical lines on image using c#

Hi!
i have a widows form in c#. what i want is to create an app that draw vertical line on a bitmap image. for that i wrote the following code:
   private void Form1_Load(object sender, EventArgs e)
            {
                  Bitmap bmOriginal = new Bitmap("kpk.bmp");
                  Rectangle cloneRect = new Rectangle(0,0 , 200, 200);
                  System.Drawing.Imaging.PixelFormat format =
                     bmOriginal.PixelFormat;
 
                  Bitmap bmTile1 = bmOriginal.Clone(cloneRect, format);
                  pictureBox1.Image = bmTile1;
              
                  }
but when i run the app is does not show the lines on image.i tried to change the values in ractangle but it didnt effect. can somebody tells me what wrong and what i need to do.?or any other C# source for that....?
thanks in advance

Try this

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

namespace LineOnImage
{
public partial class Form1 : Form
{
Bitmap bmOriginal;
public Form1()
{
InitializeComponent();

}

private void Form1_Load(object sender, EventArgs e)
{
drawImage();
}

public void drawImage()
{
Image img = Image.FromFile("kpk.bmp");
bmOriginal = new Bitmap(img.Width,img.Height);
Graphics g = Graphics.FromImage(bmOriginal);
g.DrawImage(img, 0, 0);
pictureBox1.Image = bmOriginal;
img.Dispose();
}

private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
int w = pictureBox1.Width / 2;
int h = pictureBox1.Height ;
e.Graphics.DrawLine(Pens.Red, w, 0, w, h);// this will draw a line on picturebox only - not bmOriginal
}
}
}

To draw on bmOriginal, you need to create  graphics as above
Graphics g = Graphics.FromImage(bmOriginal);
g.DrawLine(As above);
and if you want to you can save the bitmap
bmOriginal.Save("whatever.bmp", System.Drawing.Imaging.ImageFormat.Bmp);