Multi-byte characters?

[Bob Altman]

If I create a new Win32 Console project (unmanaged C++, Visual Studio 2005),
and add the following to the main program:

// Add this above the main routine
#include <windows.h // Add this at the top of the file

// Add this to the main routine
MessageBox(NULL, "A", "B", MB_OK);

The compiler (Visual Studio 2005) complains that it can't convert parameter
2 from 'const char [2]' to 'LPCWSTR'.

I don't understand why the compiler apparently thinks that I am using
multi-byte character semantics. The really bizarre part is that I have
another project that contains calls to MessageBox, and that project compiles
just fine. I've looked at the project properties in both projects, but I
can't see anything that would obviously cause one to compile correctly and
one to fail to compile.

This all began when I tried to write some code that formats a message and
sends it to the MessageBox function, like this:

ostringstream msg;
msg << "my message expression";
MessageBox(NULL, msg.str().c_str(), "Title", MB_OK);

In this case, the compiler complains that it can't convert parameter 2 from
'const char *' to 'LPCWSTR'. But, as I said, I have this identical code in
another project and it works just fine.

TIA - Bob

[Nathan Mates]

In article <eW**************@TK2MSFTNGP04.phx.gbl>,
Bob Altman <rd*@nospam.nospamwrote:

>I don't understand why the compiler apparently thinks that I am using
multi-byte character semantics.

In DevStudio, this setting can be changed by right-clicking on your
project, selecting properties, then going to Configuration Properties
-General -Character Set. Turn off unicode, and go to multibyte
character set.

Nathan Mates
--
<*Nathan Mates - personal webpage http://www.visi.com/~nathan/
# Programmer at Pandemic Studios -- http://www.pandemicstudios.com/
# NOT speaking for Pandemic Studios. "Care not what the neighbors
# think. What are the facts, and to how many decimal places?" -R.A. Heinlein

[ewpatton]

On Jun 23, 7:05 pm, "Bob Altman" <[e-mail]:

If I create a new Win32 Console project (unmanaged C++, Visual Studio 2005),
and add the following to the main program:

// Add this above the main routine
#include <windows.h // Add this at the top of the file

// Add this to the main routine
MessageBox(NULL, "A", "B", MB_OK);

The compiler (Visual Studio 2005) complains that it can't convert parameter
2 from 'const char [2]' to 'LPCWSTR'.

I don't understand why the compiler apparently thinks that I am using
multi-byte character semantics. The really bizarre part is that I have
another project that contains calls to MessageBox, and that project compiles
just fine. I've looked at the project properties in both projects, but I
can't see anything that would obviously cause one to compile correctly and
one to fail to compile.

This all began when I tried to write some code that formats a message and
sends it to the MessageBox function, like this:

ostringstream msg;
msg << "my message expression";
MessageBox(NULL, msg.str().c_str(), "Title", MB_OK);

In this case, the compiler complains that it can't convert parameter 2 from
'const char *' to 'LPCWSTR'. But, as I said, I have this identical code in
another project and it works just fine.

TIA - Bob

You can also put L in front of the string to tell the compiler it
should be expressed as a Unicode string rather than an ASCII string.

[SvenC]

Hi,

If I create a new Win32 Console project (unmanaged C++, Visual Studio
2005), and add the following to the main program:

// Add this above the main routine
#include <windows.h // Add this at the top of the file

// Add this to the main routine
MessageBox(NULL, "A", "B", MB_OK);

The compiler (Visual Studio 2005) complains that it can't convert
parameter 2 from 'const char [2]' to 'LPCWSTR'.

Enclose all strings in _T() that ensures that the correct character type
(char or wchar_t) is used.

I don't understand why the compiler apparently thinks that I am using
multi-byte character semantics. The really bizarre part is that I
have another project that contains calls to MessageBox, and that
project compiles just fine. I've looked at the project properties in
both projects, but I can't see anything that would obviously cause
one to compile correctly and one to fail to compile.

Project properties -Configuration Properties -General : Character Set

This all began when I tried to write some code that formats a message
and sends it to the MessageBox function, like this:

ostringstream msg;
msg << "my message expression";
MessageBox(NULL, msg.str().c_str(), "Title", MB_OK);

In this case, the compiler complains that it can't convert parameter
2 from 'const char *' to 'LPCWSTR'. But, as I said, I have this
identical code in another project and it works just fine.

Define t-versions of those STL types based on TCHAR

#include <tchar.h>
#include <string>
#include <sstream>

typedef std::basic_ostringstream<TCHARtstringstream;
typedef std::basic_string<TCHARtstring;

tstringstream msg;
msg << _T("my message expression");
MessageBox(NULL, msg.c_str(), _T("Title"), MB_OK);

The above compiles with both Unicode and Multi byte settings.

--
SvenC

[Bob Altman]

Mega cool. Thanks!!!

- Bob

"SvenC" <Sv***@community.nospamwrote in message
news:Ou**************@TK2MSFTNGP05.phx.gbl...

Hi,

>If I create a new Win32 Console project (unmanaged C++, Visual Studio
2005), and add the following to the main program:

// Add this above the main routine
#include <windows.h // Add this at the top of the file

// Add this to the main routine
MessageBox(NULL, "A", "B", MB_OK);

The compiler (Visual Studio 2005) complains that it can't convert
parameter 2 from 'const char [2]' to 'LPCWSTR'.

Enclose all strings in _T() that ensures that the correct character type
(char or wchar_t) is used.

>I don't understand why the compiler apparently thinks that I am using
multi-byte character semantics. The really bizarre part is that I
have another project that contains calls to MessageBox, and that
project compiles just fine. I've looked at the project properties in
both projects, but I can't see anything that would obviously cause
one to compile correctly and one to fail to compile.

Project properties -Configuration Properties -General : Character Set

>This all began when I tried to write some code that formats a message
and sends it to the MessageBox function, like this:

ostringstream msg;
msg << "my message expression";
MessageBox(NULL, msg.str().c_str(), "Title", MB_OK);

In this case, the compiler complains that it can't convert parameter
2 from 'const char *' to 'LPCWSTR'. But, as I said, I have this
identical code in another project and it works just fine.

Define t-versions of those STL types based on TCHAR

#include <tchar.h>
#include <string>
#include <sstream>

typedef std::basic_ostringstream<TCHARtstringstream;
typedef std::basic_string<TCHARtstring;

tstringstream msg;
msg << _T("my message expression");
MessageBox(NULL, msg.c_str(), _T("Title"), MB_OK);

The above compiles with both Unicode and Multi byte settings.

--
SvenC