Selects an object into the device context.
CPen* SelectObject( CPen* pPen);CBrush* SelectObject( CBrush* pBrush);virtual CFont* SelectObject( CFont* pFont);CBitmap* SelectObject( CBitmap* pBitmap);int SelectObject( CRgn* pRgn);CGdiObject* SelectObject( CGdiObject* pObject);
A pointer to the object being replaced. This is a pointer to an object of one of the classes derived from CGdiObject, such as CPen, depending on which version of the function is used. The return value is NULL if there is an error. This function may return a pointer to a temporary object. This temporary object is only valid during the processing of one Windows message. For more information, see CGdiObject::FromHandle.
The version of the member function that takes a region parameter performs the same task as the SelectClipRgn member function. Its return value can be any of the following:
COMPLEXREGION New clipping region has overlapping borders.
ERROR Device context or region is not valid.
NULLREGION New clipping region is empty.
SIMPLEREGION New clipping region has no overlapping borders.
Class CDC provides five versions specialized for particular kinds of GDI objects, including pens, brushes, fonts, bitmaps, and regions. The newly selected object replaces the previous object of the same type. For example, if pObject of the general version of SelectObject points to a CPen object, the function replaces the current pen with the pen specified by pObject.
An application can select a bitmap into memory device contexts only and into only one memory device context at a time. The format of the bitmap must either be monochrome or compatible with the device context; if it is not, SelectObject returns an error.
For Windows 3.1 and later, the SelectObject function returns the same value whether it is used in a metafile or not. Under previous versions of Windows, SelectObject returned a nonzero value for success and 0 for failure when it was used in a metafile.