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 CreateDialogParam

The CreateDialogParam function creates a modeless dialog box from a dialog box template resource. Before displaying the dialog box, the function passes an application-defined value to the dialog box procedure as the lParam parameter of the WM_INITDIALOG message. An application can use this value to initialize dialog box controls.

Syntax

    HWND CreateDialogParam(  
        HINSTANCE   hInstance,
        LPCTSTR     lpTemplateName,
        HWND        hWndParent,
        DLGPROC     lpDialogFunc,
        LPARAM      dwInitParam
    );

Parameters

• hInstance
  [in] Handle to the module whose executable file contains the dialog box template.
• lpTemplateName
  [in] Specifies the dialog box template. This parameter is either the pointer to a null-terminated character string that specifies the name of the dialog box template or an integer value that specifies the resource identifier of the dialog box template. If the parameter specifies a resource identifier, its high-order word must be zero and low-order word must contain the identifier. You can use the MAKEINTRESOURCE macro to create this value.
• hWndParent
  [in] Handle to the window that owns the dialog box.
• lpDialogFunc
  [in] Pointer to the dialog box procedure. For more information about the dialog box procedure, see DialogProc.
• dwInitParam
  [in] Specifies the value to pass to the dialog box procedure in the lParam parameter in the WM_INITDIALOG message.

Return Value

If the function succeeds, the return value is the window handle to the dialog box.

If the function fails, the return value is NULL. To get extended error information, call GetLastError.

Remarks

The CreateDialogParam function uses the CreateWindowEx function to create the dialog box. CreateDialogParam then sends a WM_INITDIALOG message (and a WM_SETFONT message if the template specifies the DS_SETFONT or DS_SHELLFONT style) to the dialog box procedure. The function displays the dialog box if the template specifies the [WS_VISIBLE] style. Finally, CreateDialogParam returns the window handle of the dialog box.

After CreateDialogParam returns, the application displays the dialog box (if it is not already displayed) using the ShowWindow function. The application destroys the dialog box by using the DestroyWindow function. To support keyboard navigation and other dialog box functionality, the message loop for the dialog box must call the IsDialogMessage function.

Windows 95/98/Me:The system can support a maximum of 255 controls per dialog box template. To place more than 255 controls in a dialog box, create the controls in the WM_INITDIALOG message handler rather than placing them in the template.

Windows 95/98/Me: CreateDialogParamW is supported by the Microsoft Layer for Unicode. To use this, you must add certain files to your application, as outlined in Microsoft Layer for Unicode on Windows 95/98/Me Systems .

Function Information

• Minimum DLL Version user32.dll
• Header Declared in Winuser.h, include Windows.h
• Import library User32.lib
• Minimum operating systems Windows 95, Windows NT 3.1
• Unicode Implemented as ANSI and Unicode versions.

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time