how to make a webcam to take photos automatically using the .net C# program

 using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace WebCam_Capture
{
 ///

  // property variables
  private int m_TimeToCapture_milliseconds = 100;
  private int m_Width = 320;
  private int m_Height = 240;
  private int mCapHwnd;
  private ulong m_FrameNumber = 0;

  // global variables to make the video capture go faster
  private WebCam_Capture.WebcamEventArgs x = new WebCam_Capture.WebcamEventArgs();
  private IDataObject tempObj;
  private System.Drawing.Image tempImg;
  private bool bStopped = true;

  // event delegate
  public delegate void WebCamEventHandler (object source, WebCam_Capture.WebcamEventArgs e);
  // fired when a new image is captured
  public event WebCamEventHandler ImageCaptured;

  #region API Declarations

  [DllImport("user32", EntryPoint="SendMessage")]
  public static extern int SendMessage(int hWnd, uint Msg, int wParam, int lParam);

  [DllImport("avicap32.dll", EntryPoint="capCreateCaptureWindowA")]
  public static extern int capCreateCaptureWindowA(string lpszWindowName, int dwStyle, int X, int Y, int nWidth, int nHeight, int hwndParent, int nID);

  [DllImport("user32", EntryPoint="OpenClipboard")]
  public static extern int OpenClipboard(int hWnd);

  [DllImport("user32", EntryPoint="EmptyClipboard")]
  public static extern int EmptyClipboard();

  [DllImport("user32", EntryPoint="CloseClipboard")]
  public static extern int CloseClipboard();

  #endregion

  #region API Constants

  public const int WM_USER = 1024;

  public const int WM_CAP_CONNECT = 1034;
  public const int WM_CAP_DISCONNECT = 1035;
  public const int WM_CAP_GET_FRAME = 1084;
  public const int WM_CAP_COPY = 1054;

  public const int WM_CAP_START = WM_USER;

  public const int WM_CAP_DLG_VIDEOFORMAT = WM_CAP_START + 41;
  public const int WM_CAP_DLG_VIDEOSOURCE = WM_CAP_START + 42;
  public const int WM_CAP_DLG_VIDEODISPLAY = WM_CAP_START + 43;
  public const int WM_CAP_GET_VIDEOFORMAT = WM_CAP_START + 44;
  public const int WM_CAP_SET_VIDEOFORMAT = WM_CAP_START + 45;
  public const int WM_CAP_DLG_VIDEOCOMPRESSION = WM_CAP_START + 46;
  public const int WM_CAP_SET_PREVIEW = WM_CAP_START + 50;

  #endregion

  #region NOTES

  /*
   * If you want to allow the user to change the display size and
   * color format of the video capture, call:
   * SendMessage (mCapHwnd, WM_CAP_DLG_VIDEOFORMAT, 0, 0);
   * You will need to requery the capture device to get the new settings
  */

  #endregion

  public WebCamCapture()
  {
   // This call is required by the Windows.Forms Form Designer.
   InitializeComponent();
  }

  ///

  ///

    if( components != null )
     components.Dispose();
   }
   base.Dispose( disposing );
  }

  #region Component Designer generated code
  ///

  }
  #endregion

  #region Control Properties

  ///

   set
   { m_TimeToCapture_milliseconds = value; }
  }

  ///

  ///

   set
   { m_Width = value; }
  }

  ///

   set
   { m_FrameNumber = value; }
  }

  #endregion

  #region Start and Stop Capture Functions

  ///

    // setup a capture window
    mCapHwnd = capCreateCaptureWindowA("WebCap", 0, 0, 0, m_Width, m_Height, this.Handle.ToInt32(), 0);

    // connect to the capture device
    Application.DoEvents();
    SendMessage(mCapHwnd, WM_CAP_CONNECT, 0, 0);
    SendMessage(mCapHwnd, WM_CAP_SET_PREVIEW, 0, 0);

    // set the frame number
    m_FrameNumber = FrameNum;

    // set the timer information
    this.timer1.Interval = m_TimeToCapture_milliseconds;
    bStopped = false;
    this.timer1.Start();
   }

   catch (Exception excep)
   {
    MessageBox.Show("An error ocurred while starting the video capture. Check that your webcamera is connected properly and turned on.\r\n\n" + excep.Message);
    this.Stop();
   }
  }

  ///

    // disconnect from the video source
    Application.DoEvents();
    SendMessage(mCapHwnd, WM_CAP_DISCONNECT, 0, 0);
   }

   catch (Exception excep)
   { // don't raise an error here.
   }

  }

  #endregion

  #region Video Capture Code

  ///

    // get the next frame;
    SendMessage(mCapHwnd, WM_CAP_GET_FRAME, 0, 0);

    // copy the frame to the clipboard
    SendMessage(mCapHwnd, WM_CAP_COPY, 0, 0);

    // paste the frame into the event args image
    if (ImageCaptured != null)
    {
     // get from the clipboard
     tempObj = Clipboard.GetDataObject();
     tempImg = (System.Drawing.Bitmap) tempObj.GetData(System.Windows.Forms.DataFormats.Bitmap);

     /*
     * For some reason, the API is not resizing the video
     * feed to the width and height provided when the video
     * feed was started, so we must resize the image here
     */
     x.WebCamImage = tempImg.GetThumbnailImage(m_Width, m_Height, null, System.IntPtr.Zero);

     // raise the event
     this.ImageCaptured(this, x);
    }  

    // restart the timer
    Application.DoEvents();
    if (! bStopped)
     this.timer1.Start();
   }

   catch (Exception excep)
   {
    MessageBox.Show("An error ocurred while capturing the video image. The video capture will now be terminated.\r\n\n" + excep.Message);
    this.Stop(); // stop the process
   }
  }

  #endregion