/// <summary>
/// Changes an attribute of the specified window. The function also sets a value at the specified
/// offset in the extra window memory.
/// </summary>
/// <param name="hWnd">A handle to the window and, indirectly, the class to which the window belongs.
/// The SetWindowLongPtr function fails if the process that owns the window specified by the
/// <paramref name="hWnd"/> parameter is at a higher process privilege in the UIPI hierarchy than the
/// process the calling thread resides in.</param>
/// <param name="nIndex">The zero-based offset to the value to be set. Valid values are in the range zero
/// through the number of bytes of extra window memory, minus the size of a LONG_PTR. To set any other value,
/// specify one of the following values.
///
/// <list type="table">
/// <listheader><term>Value</term><term>Meaning</term></listheader>
/// <item><term>GWL_EXSTYLE(-20)</term><term>Sets a new extended window style.</term></item>
/// <item><term>GWLP_HINSTANCE(-6)</term><term>Sets a new application instance handle.</term></item>
/// <item><term>GWLP_ID(-12)</term><term>Sets a new identifier of the child window.The window cannot be a top-level window.</term></item>
/// <item><term>GWL_STYLE (-16)</term><term>Sets a new window style.</term></item>
/// <item><term>GWLP_USERDATA</term><term>Sets the user data associated with the window.This data is intended for use by the application that created the window. Its value is initially zero.</term></item>
/// <item><term>GWLP_WNDPROC (-4)</term><term>Sets a new address for the window procedure.</term></item>
/// </list>
///
/// The following values are also available when the hWnd parameter identifies a dialog box.
///
/// <list type="table">
/// <listheader><term>Value</term><term>Meaning</term></listheader>
/// <item><term>DWLP_DLGPROC (DWLP_MSGRESULT + sizeof(LRESULT))</term><term>Sets the new pointer to the dialog box procedure.</term></item>
/// <item><term>DWLP_MSGRESULT (0)</term><term>Sets the return value of a message processed in the dialog box procedure.</term></item>
/// <item><term>DWLP_USER (DWLP_DLGPROC + sizeof(DLGPROC))</term><term>Sets new extra info</term></item>
/// </list>
///
/// </param>
/// <param name="dwNewLong">The replacement value.</param>
/// <returns>
/// <para>If the function succeeds, the return value is the previous value of the specified offset.</para>
/// <para>If the function fails, the return value is zero. To get extended error information, call GetLastError.</para>
/// <para>If the previous value is zero and the function succeeds, the return value is zero, but the function does
/// not clear the last error information. To determine success or failure, clear the last error information by
/// calling SetLastError with 0, then call SetWindowLongPtr. Function failure will be indicated by a return value of
/// zero and a GetLastError result that is nonzero.</para>
/// </returns>
/// <remarks>
/// <list type="bullet">
/// <item>The return type, and the type of <paramref name="dwNewLong"/> are both LONG_PTR.
/// LONG_PTR is defined as <code>__int64</code> on 64-bit platforms, and it is defined as <code>long</code>
/// on 32-bit platforms. This definition fits nicely with now <see cref="IntPtr"/> works on 32-bit vs. 64-bit
/// platforms.</item>
/// <item>Windows XP/2000: The SetWindowLongPtr function fails if the window specified by the
/// <paramref name="hWnd"/> parameter does not belong to the same process as the calling thread.</item>
/// <item>When compiling for 32-bit Windows, SetWindowLongPtr is defined as a call to the SetWindowLong function.</item>
/// <item>
/// <para>Certain window data is cached, so changes you make using SetWindowLongPtr will not take effect until you call
/// the SetWindowPos function.</para>
/// <para>If you use SetWindowLongPtr with the <see cref="WindowLongIndexFlags.GWLP_WNDPROC"/> index to replace the window procedure,
/// the window procedure must conform to the guidelines specified in the description of the WindowProc callback function.</para>
/// <para>If you use SetWindowLongPtr with the <see cref="WindowLongIndexFlags.DWLP_MSGRESULT"/> index to set the return value for a
/// message processed by a dialog box procedure, the dialog box procedure should return TRUE directly afterward. Otherwise, if you call
/// any function that results in your dialog box procedure receiving a window message, the nested window message could overwrite the return value
/// you set by using <see cref="WindowLongIndexFlags.DWLP_MSGRESULT"/>.</para>
/// <para>Calling SetWindowLongPtr with the <see cref="WindowLongIndexFlags.GWLP_WNDPROC"/> index creates a subclass of the window
/// class used to create the window. An application can subclass a system class, but should not subclass a window class created by another process.
/// The SetWindowLongPtr function creates the window subclass by changing the window procedure associated with a particular
/// window class, causing the system to call the new window procedure instead of the previous one. An application must pass
/// any messages not processed by the new window procedure to the previous window procedure by calling CallWindowProc.
/// This allows the application to create a chain of window procedures.</para>
/// <para>Reserve extra window memory by specifying a nonzero value in the <see cref="WNDCLASSEX.cbWndExtra"/> member of the
/// <see cref="WNDCLASSEX"/> structure used with the RegisterClassEx function.</para>
/// <para>Do not call SetWindowLongPtr with the <see cref="WindowLongIndexFlags.GWLP_HWNDPARENT"/> index to change the parent of a
/// child window. Instead, use the SetParent function.</para>
/// <para>If the window has a class style of <see cref="ClassStyles.CS_CLASSDC"/> or <see cref="ClassStyles.CS_PARENTDC"/>, do not set
/// the extended window styles <see cref="WindowStylesEx.WS_EX_COMPOSITED"/> or <see cref="WindowStylesEx.WS_EX_LAYERED"/>.</para>
/// <para>Calling SetWindowLongPtr to set the style on a progressbar will reset its position.</para>
/// </item>
/// </list>
/// </remarks>
public static unsafe void *SetWindowLongPtr(IntPtr hWnd, WindowLongIndexFlags nIndex, void *dwNewLong)
{
if (IntPtr.Size == 8)
{
return(SetWindowLongPtr64(hWnd, nIndex, dwNewLong));
}
else
{
var dwValue = (SetWindowLongFlags)(int)dwNewLong;
return((void *)SetWindowLong(hWnd, nIndex, dwValue));
}
}
public static extern int GetWindowLong(IntPtr hWnd, WindowLongIndexFlags nIndex);
public static extern int SetWindowLong(IntPtr hWnd, WindowLongIndexFlags nIndex, SetWindowLongFlags dwNewLong);
public static extern int GetWindowLong(IntPtr hWnd, WindowLongIndexFlags nIndex);
public static extern int SetWindowLong(IntPtr hWnd, WindowLongIndexFlags nIndex, SetWindowLongFlags dwNewLong);
public int GetWindowLong(IntPtr hWnd, WindowLongIndexFlags nIndex) => GetWindowLong(hWnd, nIndex);
public int SetWindowLong(IntPtr hWnd, WindowLongIndexFlags nIndex, SetWindowLongFlags dwNewLong) => SetWindowLong(hWnd, nIndex, dwNewLong);
