CREATESTRUCT

The CREATESTRUCT structure defines the initialization parameters passed to the window procedure of an application.

typedef struct tagCREATESTRUCT { // cs

LPVOID lpCreateParams;

HINSTANCE hInstance;

HMENU hMenu;

HWND hwndParent;

int cy;

int cx;

int y;

int x;

LONG style;

LPCTSTR lpszName;

LPCTSTR lpszClass;

DWORD dwExStyle;

} CREATESTRUCT;

Members

lpCreateParams

Points to data to be used for creating the window.

Windows NT: This member is the address of a SHORT (16_bit) value that specifies the size, in bytes, of the window creation data. The value is immediately followed by the creation data. For more information, see the following Remarks section.

hInstance

Identifies the module that owns the new window.

hMenu

Identifies the menu to be used by the new window.

hwndParent

Identifies the parent window, if the window is a child window. If the window is owned, this member identifies the owner window. If the window is not a child or owned window, this member is NULL.

cy

Specifies the height of the new window, in pixels.

cx

Specifies the width of the new window, in pixels.

y

Specifies the y-coordinate of the upper left corner of the new window. If the new window is a child window, coordinates are relative to the parent window. Otherwise, the coordinates are relative to the screen origin.

x

Specifies the x-coordinate of the upper left corner of the new window. If the new window is a child window, coordinates are relative to the parent window. Otherwise, the coordinates are relative to the screen origin.

style

Specifies the style for the new window.

lpszName

Points to a null-terminated string that specifies the name of the new window.

lpszClass

Points to a null-terminated string that specifies the class name of the new window.

dwExStyle

Specifies the extended style for the new window.

Remarks

Windows NT: Referring to the lpCreateParams member of the CREATESTRUCT structure, because the pointer may not be DWORD aligned, an application should access the data using a pointer that has been declared using the UNALIGNED type, as shown in the following example:

typedef struct tagMyData {

. . .;// define creation data here

} MYDATA;

typedef struct tagMyDlgData {

SHORT cbExtra;

MYDATA myData;

} MYDLGDATA, UNALIGNED *PMYDLGDATA;

PMYDLGDATA pMyDlgdata =

(PMYDLGDATA) (((LPCREATESTRUCT) lParam)->lpcreateParams);

See Also

CreateWindow, CreateWindowEx