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String Conversion Macros

These macros provide string conversion features.

ATL and MFC String Conversion Macros

The string conversion macros discussed here are valid for both ATL and MFC. For more information on MFC string conversion, see TN059: Using MFC MBCS/Unicode Conversion Macros and MFC Macros and Globals.

DEVMODE and TEXTMETRIC String Conversion Macros

These macros create a copy of a DEVMODE or TEXTMETRIC structure and convert the strings within the new structure to a new string type. The macros allocate memory on the stack for the new structure and return a pointer to the new structure.

MACRONAME( address_of_structure )

Remarks

For example:

DEVMODEW* lpw = DEVMODEA2W(lpa);

and:

TEXTMETRICW* lptmw = TEXTMETRICA2W(lptma);

In the macro names, the string type in the source structure is on the left (for example, A) and the string type in the destination structure is on the right (for example, W). A stands for LPSTR, OLE stands for LPOLESTR, T stands for LPTSTR, and W stands for LPWSTR.

Thus, DEVMODEA2W copies a DEVMODE structure with LPSTR strings into a DEVMODE structure with LPWSTR strings, TEXTMETRICOLE2T copies a TEXTMETRIC structure with LPOLESTR strings into a TEXTMETRIC structure with LPTSTR strings, and so on.

The two strings converted in the DEVMODE structure are the device name (dmDeviceName) and the form name (dmFormName). The DEVMODE string conversion macros also update the structure size (dmSize).

The four strings converted in the TEXTMETRIC structure are the first character (tmFirstChar), the last character (tmLastChar), the default character (tmDefaultChar), and the break character (tmBreakChar).

The behavior of the DEVMODE and TEXTMETRIC string conversion macros depends on the compiler directive in effect, if any. If the source and destination types are the same, no conversion takes place. Compiler directives change T and OLE as follows:

Compiler directive in effect T becomes OLE becomes
none A W
_UNICODE W W
OLE2ANSI A A
_UNICODE and OLE2ANSI W A

The following table lists the DEVMODE and TEXTMETRIC string conversion macros.

DEVMODE macro TEXTMETRIC macro
DEVMODEA2W TEXTMETRICA2W
DEVMODEOLE2T TEXTMETRICOLE2T
DEVMODET2OLE TEXTMETRICT2OLE
DEVMODEW2A TEXTMETRICW2A

See also

Macros