WinQueryWindowDC

This function returns the device context for a given window.

Syntax

WinQueryWindowDC(hwnd)

Parameters

hwnd (HWND) - input

Window handle.

Returns

hdc (HDC) - returns

Device-context handle.

NULLHANDLE

Either WinOpenWindowDC has not been called for this window, or an error has occurred.

Other

Device context handle.

Errors

Possible returns from WinGetLastError

PMERR_INVALID_HWND (0x1001)

An invalid window handle was specified.

Remarks

A handle is returned only if a device context has been opened for the window with WinOpenWindowDC.

Example Code

This example shows how to check if WinOpenWindowDC has been called for this window.

#define INCL_WINWINDOWMGR
#include <OS2.H>

HWND  hwndClient;           /* window handle. */

if(WinQueryWindowDC(hwndClient))
{
     /*  ...    */
}

Definition

#define INCL_WINWINDOWMGR /* Or use INCL_WIN, INCL_PM, */
#include <os2.h>

HWND    hwnd;  /*  Window handle. */
HDC     hdc;   /*  Device-context handle. */

hdc = WinQueryWindowDC(hwnd);

Related Functions

• WinEnableWindow
• WinIsThreadActive
• WinIsWindow
• WinIsWindowEnabled
• WinQueryDesktopWindow
• WinQueryObjectWindow
• WinQueryWindowProcess
• WinQueryWindowRect
• WinWindowFromDC
• WinWindowFromID
• WinWindowFromPoint