C# - How to turn your webcam on (full code)

Hi again!
How are you? This time I want to show you how to turn your webcam on.
Follow these steps to get it done:

1)      Create a VS C# project

2)      Add a “button” and a “picturebox” to your Form

3)      Adapt the following to yours:

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

using System.Runtime.InteropServices;

using System.Collections;

namespace SandBox

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)

        {

            TCamDevice w = new TCamDevice(0);

            w.ShowWindow(pictureBox1);

        }

    }

    public class DeviceManager

    {

        [DllImport("avicap32.dll")]

        protected static extern bool capGetDriverDescriptionA(short wDriverIndex,

            [MarshalAs(UnmanagedType.VBByRefStr)]ref String lpszName,

           int cbName, [MarshalAs(UnmanagedType.VBByRefStr)] ref String lpszVer, int cbVer);

        static ArrayList devices = new ArrayList();

        public static TCamDevice[] GetAllDevices()

        {

            String dName = "".PadRight(100);

            String dVersion = "".PadRight(100);

            for (short i = 0; i < 10; i++)

            {

                if (capGetDriverDescriptionA(i, ref dName, 100, ref dVersion, 100))

                {

                    TCamDevice d = new TCamDevice(i);

                    d.Name = dName.Trim();

                    d.Version = dVersion.Trim();

                    devices.Add(d);

                }

            }

            return (TCamDevice[])devices.ToArray(typeof(TCamDevice));

        }

        public static TCamDevice GetDevice(int deviceIndex)

        {

            return (TCamDevice)devices[deviceIndex];

        }

    }

    public class TCamDevice

    {

        private const short WM_CAP = 0x400;

        private const int WM_CAP_DRIVER_CONNECT = 0x40a;

        private const int WM_CAP_DRIVER_DISCONNECT = 0x40b;

        private const int WM_CAP_EDIT_COPY = 0x41e;

        private const int WM_CAP_SET_PREVIEW = 0x432;

        private const int WM_CAP_SET_OVERLAY = 0x433;

        private const int WM_CAP_SET_PREVIEWRATE = 0x434;

        private const int WM_CAP_SET_SCALE = 0x435;

        private const int WS_CHILD = 0x40000000;

        private const int WS_VISIBLE = 0x10000000;

        [DllImport("avicap32.dll")]

        protected static extern int capCreateCaptureWindowA([MarshalAs(UnmanagedType.VBByRefStr)] ref string lpszWindowName,

            int dwStyle, int x, int y, int nWidth, int nHeight, int hWndParent, int nID);

        [DllImport("user32", EntryPoint = "SendMessageA")]

        protected static extern int SendMessage(int hwnd, int wMsg, int wParam, [MarshalAs(UnmanagedType.AsAny)] object lParam);

        [DllImport("user32")]

        protected static extern int SetWindowPos(int hwnd, int hWndInsertAfter, int x, int y, int cx, int cy, int wFlags);

        [DllImport("user32")]

        protected static extern bool DestroyWindow(int hwnd);

        int index;

        int deviceHandle;

        public TCamDevice(int index)

        {

            this.index = index;

        }

        private string _name;

        public string Name

        {

            get { return _name; }

            set { _name = value; }

        }

        private string _version;

        public string Version

        {

            get { return _version; }

            set { _version = value; }

        }

        public override string ToString()

        {

            return this.Name;

        }

        /// <summary>

        /// To Initialize the device

        /// </summary>

        /// <param name="windowHeight">Height of the Window</param>

        /// <param name="windowWidth">Width of the Window</param>

        /// <param name="handle">The Control Handle to attach the device</param>

        public void Init(int windowHeight, int windowWidth, int handle)

        {

            string deviceIndex = Convert.ToString(this.index);

            deviceHandle = capCreateCaptureWindowA(ref deviceIndex, WS_VISIBLE | WS_CHILD, 0, 0, windowWidth, windowHeight, handle, 0);

            if (SendMessage(deviceHandle, WM_CAP_DRIVER_CONNECT, this.index, 0) > 0)

            {

                SendMessage(deviceHandle, WM_CAP_SET_SCALE, -1, 0);

                SendMessage(deviceHandle, WM_CAP_SET_PREVIEWRATE, 0x42, 0);

                SendMessage(deviceHandle, WM_CAP_SET_PREVIEW, -1, 0);

                SetWindowPos(deviceHandle, 1, 0, 0, windowWidth, windowHeight, 6);

            }

        }

        /// <summary>

        /// Shows the webcam preview in the control

        /// </summary>

        /// <param name="windowsControl">Control to attach the webcam preview</param>

        public void ShowWindow(global::System.Windows.Forms.Control windowsControl)

        {

            Init(windowsControl.Height, windowsControl.Width, windowsControl.Handle.ToInt32());

        }

        /// <summary>

        /// Stop the webcam and destroy the handle

        /// </summary>

        public void Stop()

        {

            SendMessage(deviceHandle, WM_CAP_DRIVER_DISCONNECT, this.index, 0);

            DestroyWindow(deviceHandle);

        }

    }

   

}

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