DialogBoxParam

The DialogBoxParam function creates a modal 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.

int DialogBoxParam(

HINSTANCE hInstance, // handle to application instance
LPCTSTR lpTemplateName, // identifies dialog box template
HWND hWndParent, // handle to owner window
DLGPROC lpDialogFunc, // pointer to dialog box procedure
LPARAM dwInitParam // initialization value
);  

Parameters

hInstance

Identifies an instance of the module whose executable file contains the dialog box template.

lpTemplateName

Identifies 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 its low-order word must contain the identifier. You can use the MAKEINTRESOURCE macro to create this value.

hWndParent

Identifies the window that owns the dialog box.

lpDialogFunc

Points to the dialog box procedure. For more information about the dialog box procedure, see the DialogProc callback function.

dwInitParam

Specifies the value to pass to the dialog box in the lParam parameter of the WM_INITDIALOG message.

Return Values

If the function succeeds, the return value is the value of the nResult parameter specified in the call to the EndDialog function used to terminate the dialog box.

If the function fails, the return value is -1.

Remarks

The DialogBoxParam function uses the CreateWindowEx function to create the dialog box. DialogBoxParam then sends a WM_INITDIALOG message (and a WM_SETFONT message if the template specifies the DS_SETFONT style) to the dialog box procedure. The function displays the dialog box (regardless of whether the template specifies the WS_VISIBLE style), disables the owner window, and starts its own message loop to retrieve and dispatch messages for the dialog box.

When the dialog box procedure calls the EndDialog function, DialogBoxParam destroys the dialog box, ends the message loop, enables the owner window (if previously enabled), and returns the nResult parameter specified by the dialog box procedure when it called EndDialog.

Windows 95: The system can support a maximum of 16,364 window handles.

See Also

CreateWindowEx, DialogBox, DialogBoxIndirect, DialogBoxIndirectParam, DialogProc, EndDialog, MAKEINTRESOURCE, WM_INITDIALOG, WM_SETFONT