C#

<br />
/* I have a string value (FilePath) parameter which I want to send to the  function ClickHandler which gets invoked whenerever someone clicks on a PictureBox <br />
*/<br />
string FilePath; //Has file path info<br />
picBoxes[index].Click += new System.EventHandler(ClickHandler);<br />
<br />
...<br />
...<br />
<br />
// Signature of ClickHandler method is as follows<br />
public void ClickHandler(Object sender, System.EventArgs e)<br />
{<br />
  // I can get the handle to the PictureBox which was clicked by the user<br />
  // as follows<br />
<br />
  PictureBox pbx = new PictureBox();<br />
  pbx = (PictureBox) ((System.Windows.Forms.PictureBox)sender);<br />
<br />
  // How do I access FilePath ?<br />
<br />
}<br />
<br />

public static bool CovertToGray(Bitmap bmp)<br />
        {<br />
           <br />
            BitmapData bmData = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height),<br />
                ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);<br />
            int stride = bmData.Stride;<br />
            System.IntPtr Scan0 = bmData.Scan0;<br />
        unsafe<br />
            {<br />
                byte* p = (byte*)(void*)Scan0;<br />
                byte red, green, blue;<br />
                int nOffset = stride - bmp.Width * 3;<br />
                for (int y = 0; y < bmp.Height; ++y)<br />
                {<br />
                    for (int x = 0; x < bmp.Width; ++x)<br />
                    {<br />
                        blue = p[0];<br />
                        green = p[1];<br />
                        red = p[2];<br />
                        p[0] = p[1] = p[2] = (byte)(.299 * red<br />
                            + .587 * green + .114 * blue);<br />
                        p += 3;<br />
                    }<br />
                    p += nOffset;<br />
                }<br />
            }<br />
            bmp.UnlockBits(bmData);<br />
            return true;<br />
        }