IPicture::get_CurDC method (ocidl.h)
Retrieves the handle of the current device context. This property is valid only for bitmap pictures.
Syntax
HRESULT get_CurDC(
[out] HDC *phDC
);
Parameters
[out] phDC
A pointer a variable that receives the device context.
Return value
This method supports the standard return value E_FAIL, as well as the following values.
| Return code | Description |
|---|---|
|
The attribute bits were returned successfully. |
|
The value of phDC is not valid. For example, it may be NULL. |
Remarks
The CurDC property and the IPicture::SelectPicture method exist to circumvent restrictions in Windows; specifically, that an object can only be selected into exactly one device context at a time. In some cases, a picture object may be permanently selected into a particular device context (for example, a control may use a certain picture for a background). To use this picture property elsewhere, it must be temporarily deselected from its old device context, selected into the new device context for the operation, then reselected back into the old device context. The IPicture::get_CurDC method returns the device context handle into which the picture is currently selected. The IPicture::SelectPicture method selects the picture into a new device context, returning the old device context and the picture's GDI handle. The caller should select the picture back into the old device context when the caller is done with it, as is normal for Windows code.
Notes to Callers
The caller always owns any device contexts passed between it and the picture object. Because the picture object maintains a copy of the HDC, the caller should use a memory device context (created with the CreateCompatibleDC function) and not a screen device context (from GetDC, CreateDC, or BeginPaint), because the screen device contexts are a limited system resource.Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Target Platform | Windows |
| Header | ocidl.h |