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CreateWindow (user32)
 
.
Summary
The CreateWindow function creates an overlapped, pop-up, or child window. It specifies the window class, window title, window style, and (optionally) the initial position and size of the window. The function also specifies the window's parent or owner, if any, and the window's menu. To use extended window styles in addition to the styles supported by CreateWindow, use the CreateWindowEx function.

C# Signature:

[DllImport("user32.dll", SetLastError=true)]
static extern IntPtr CreateWindow(
       string lpClassName,
       string lpWindowName,
       uint dwStyle,
       int x,
       int y,
       int nWidth,
       int nHeight,
       IntPtr hWndParent,
       IntPtr hMenu,
       IntPtr hInstance,
       IntPtr lpParam);

Summary

VB Signature:

C# Signature:

[DllImport("user32.dll", EntryPoint="CreateWindowStation", CharSet=CharSet.Unicode, SetLastError=true)]
    public static extern IntPtr CreateWindowStation(
                    [MarshalAs(UnmanagedType.LPWStr)] string name,
                    [MarshalAs(UnmanagedType.U4)] int reserved,      // must be zero.
                    [MarshalAs(UnmanagedType.U4)] WINDOWS_STATION_ACCESS_MASK desiredAccess,
                    [MarshalAs(UnmanagedType.LPStruct)] SecurityAttributes attributes);

User-Defined Types:

None.

Alternative Managed API:

Windows Forms (System.Windows)

Windows Presentation Foundation (System.Windows.Forms)

Notes:

None.

Tips & Tricks:

Please add some!

Sample Code:

    [StructLayout(LayoutKind.Sequential)]
    public class SecurityAttributes
    {
    #region Struct members
    [MarshalAs(UnmanagedType.U4)]
    private int mStuctLength;

    private IntPtr mSecurityDescriptor;

Documentation

    [MarshalAs(UnmanagedType.U4)]
    private bool mInheritHandle;
    #endregion

    public SecurityAttributes()
    {
        mStuctLength = Marshal.SizeOf(typeof(SecurityAttributes));
        mSecurityDescriptor = IntPtr.Zero;
    }

    public IntPtr SecurityDescriptor
    {
        get { return mSecurityDescriptor; }
        set { mSecurityDescriptor = value; }
    }

    public bool Inherit
    {
        get { return mInheritHandle; }
        set { mInheritHandle = value; }
    }
    }
[Flags]
    internal enum WINDOWS_STATION_ACCESS_MASK : uint
    {
    WINSTA_NONE         = 0,

    WINSTA_ENUMDESKTOPS     = 0x0001,
    WINSTA_READATTRIBUTES       = 0x0002,
    WINSTA_ACCESSCLIPBOARD      = 0x0004,
    WINSTA_CREATEDESKTOP    = 0x0008,
    WINSTA_WRITEATTRIBUTES      = 0x0010,
    WINSTA_ACCESSGLOBALATOMS    = 0x0020,
    WINSTA_EXITWINDOWS      = 0x0040,
    WINSTA_ENUMERATE        = 0x0100,
    WINSTA_READSCREEN       = 0x0200,

    WINSTA_ALL_ACCESS       = ( WINSTA_ENUMDESKTOPS | WINSTA_READATTRIBUTES | WINSTA_ACCESSCLIPBOARD |
                    WINSTA_CREATEDESKTOP | WINSTA_WRITEATTRIBUTES | WINSTA_ACCESSGLOBALATOMS |
                    WINSTA_EXITWINDOWS | WINSTA_ENUMERATE | WINSTA_READSCREEN |
                    STANDARD_ACCESS.STANDARD_RIGHTS_REQUIRED),
    }

     /// <summary>
    /// Base class for the safe handles used for Windows Station and Desktop API.
    /// </summary>
    public abstract class BaseSafeHandle : SafeHandleZeroOrMinusOneIsInvalid
    {
    protected BaseSafeHandle(IntPtr handle, bool ownsHandle)
        : base(ownsHandle)
    {
        SetHandle(handle);
    }

    /// <summary>
    /// Close the native handle. The real call is dependent on whether it is
    /// a WindowsStation or a Desktop.
    /// </summary>
    /// <param name="handle">Handle to be closed.</param>
    /// <returns>true if successful, false other wise.</returns>
    protected abstract bool CloseNativeHandle(IntPtr handle);

    protected override bool ReleaseHandle()
    {
        if (IsInvalid)
        {
        return false;
        }
        bool closed = CloseNativeHandle(this.handle);
        if (closed)
        {
        SetHandle(IntPtr.Zero);
        }
        return closed;
    }

    }

public class SafeWindowStationHandle : BaseSafeHandle
    {
    public SafeWindowStationHandle(IntPtr handle, bool ownsHandle)
        : base(handle, ownsHandle)
    { }

    protected override bool CloseNativeHandle(IntPtr handle)
    {
        return WindowStationAndDesktop.CloseWindowStation(handle);
    }
    }
public static SafeWindowStationHandle CreateWindowStation(string name)
    {
        if (string.IsNullOrEmpty(name))
        {
        throw new ArgumentException("Invalid window station name", "name");
        }

        IntPtr handle = WindowStationAndDesktop.CreateWindowStation(name, 0,
                WINDOWS_STATION_ACCESS_MASK.WINSTA_ALL_ACCESS, null);
        if (handle == IntPtr.Zero)
        {
        int error = Marshal.GetLastWin32Error();
        throw new Win32Exception(error);
        }

        SafeWindowStationHandle safeHandle = new SafeWindowStationHandle(handle, true);

        return safeHandle;
    }

Alternative Managed API:

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Documentation

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