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CMetaFileDC::CreateEnhanced

Creates a device context for an enhanced-format metafile.

BOOL CreateEnhanced(
   CDC* pDCRef,
   LPCTSTR lpszFileName,
   LPCRECT lpBounds,
   LPCTSTR lpszDescription 
);

Parameters

  • pDCRef
    Identifies a reference device for the enhanced metafile.

  • lpszFileName
    Points to a null-terminated character string. Specifies the filename for the enhanced metafile to be created. If this parameter is NULL, the enhanced metafile is memory based and its contents lost when the object is destroyed or when the Win32 DeleteEnhMetaFile function is called.

  • lpBounds
    Points to a RECT data structure or a CRect object that specifies the dimensions in HIMETRIC units (in .01-millimeter increments) of the picture to be stored in the enhanced metafile.

  • lpszDescription
    Points to a zero-terminated string that specifies the name of the application that created the picture, as well as the picture's title.

Return Value

A handle of the device context for the enhanced metafile, if successful; otherwise NULL.

Remarks

This DC can be used to store a device-independent picture.

Windows uses the reference device identified by the pDCRef parameter to record the resolution and units of the device on which a picture originally appeared. If the pDCRef parameter is NULL, it uses the current display device for reference.

The left and top members of the RECT data structure pointed to by the lpBounds parameter must be smaller than the right and bottom members, respectively. Points along the edges of the rectangle are included in the picture. If lpBounds is NULL, the graphics device interface (GDI) computes the dimensions of the smallest rectangle that can enclose the picture drawn by the application. The lpBounds parameter should be supplied where possible.

The string pointed to by the lpszDescription parameter must contain a null character between the application name and the picture name and must terminate with two null characters —for example, "XYZ Graphics Editor\0Bald Eagle\0\0," where \0 represents the null character. If lpszDescription is NULL, there is no corresponding entry in the enhanced-metafile header.

Applications use the DC created by this function to store a graphics picture in an enhanced metafile. The handle identifying this DC can be passed to any GDI function.

After an application stores a picture in an enhanced metafile, it can display the picture on any output device by calling the CDC::PlayMetaFile function. When displaying the picture, Windows uses the rectangle pointed to by the lpBounds parameter and the resolution data from the reference device to position and scale the picture. The device context returned by this function contains the same default attributes associated with any new DC.

Applications must use the Win32 GetWinMetaFileBits function to convert an enhanced metafile to the older Windows metafile format.

The filename for the enhanced metafile should use the .EMF extension.

Requirements

Header: afxext.h

See Also

Concepts

CMetaFileDC Class

CMetaFileDC Members

Hierarchy Chart

CMetaFileDC::CloseEnhanced

CDC::PlayMetaFile

CloseEnhMetaFile

DeleteEnhMetaFile

GetEnhMetaFileDescription

GetEnhMetaFileHeader

GetWinMetaFileBits

PlayEnhMetaFile