MetafileHeader type

The header of a Metafile: its kind, size, resolution and bounds.

Metafile.MetafileHeader returns one, and so do the functions GetMetafileHeader, GetMetafileHeaderFromEmf and GetMetafileHeaderFromWmf, which read the header of a file, a stream or a handle. The type mirrors the GDI+ MetafileHeader class. Besides its fields it has properties that answer the usual questions about the kind of metafile.

Fields
Properties
See Also

Fields

Field	Type	Meaning
Type	GpMetafileType	The kind of metafile: WMF, placeable WMF, EMF, EMF+ only or EMF+ dual.
Size	UINT	The size of the metafile in bytes.
Version	UINT	The version of the EMF+, EMF or WMF format.
EmfPlusFlags	UINT	The EMF+ flags. Bit 0 is set when the metafile was recorded for a display.
DpiX, DpiY	Single	The horizontal and vertical resolution of the metafile, in dots per inch.
X, Y, Width, Height	Long	The bounds of the metafile in device units.
EmfPlusHeaderSize	Long	The size of the EMF+ header in the file.
LogicalDpiX, LogicalDpiY	Long	The logical resolution of the reference device context. Usually valid only for EMF+.

The structure has one more field, which holds the WMF or EMF header and is read through the properties WmfHeader and EmfHeader.

Properties

Bounds

Syntax: r = header.Bounds

Returns X, Y, Width and Height as a GpRect.

IsWmf, IsWmfPlaceable

Syntax: b = header.IsWmf

Syntax: b = header.IsWmfPlaceable

IsWmf is True for a Windows metafile of either kind, and IsWmfPlaceable only for one with a placeable header.

IsEmf, IsEmfOrEmfPlus, IsEmfPlus, IsEmfPlusDual, IsEmfPlusOnly

Syntax: b = header.IsEmf

IsEmf is True for an EMF that has no EMF+ records. IsEmfOrEmfPlus is True for an EMF or either kind of EMF+. IsEmfPlus is True for both kinds of EMF+, IsEmfPlusDual for an EMF+ that also holds the records an EMF reader understands, and IsEmfPlusOnly for one that does not.

IsDisplay

Syntax: b = header.IsDisplay

True for an EMF+ metafile that was recorded for a display device context.

WmfHeader

Syntax: h = header.WmfHeader

Returns the WMF header of a Windows metafile as a structure of the package, or a structure of zeros for another kind of metafile.

EmfHeader

Syntax: h = header.EmfHeader

Returns the EMF header of an EMF or EMF+ metafile as a structure of the package whose fields (nBytes, nRecords, nHandles and others) are those of the Windows ENHMETAHEADER structure, or a structure of zeros for a WMF.

Dim user As GdiPlusUser = GdiPlusUser()

Dim mf As Metafile = Metafile(HeaderEmf.MakeEmf(40, 30), True)
Dim header As MetafileHeader = mf.MetafileHeader

Debug.Print header.Type
Debug.Print header.IsEmf & " " & header.IsEmfOrEmfPlus & " " & header.IsEmfPlus & " " & header.IsWmf
Debug.Print header.X & " " & header.Y & " " & header.Width & " " & header.Height
Debug.Print header.Bounds.Width
Debug.Print header.EmfHeader.nRecords
' Output:
' 3
' True True False False
' 0 0 40 30
' 40
' 3