Message Box

Hey,

I have this line to show a message box:
MessageBox(NULL, size, "Size", MB_OK);

size is a parameter (float) passed into a function.

How can I get a float variable to show in a message box.
it gives me an error.

Thanks,

you will need to convert your float to a char*.

there are several ways to do this:

C:

Code:

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#include <stdio.h>

// this code doesn't check for overflows.  could be bad.
char szBuffer[32];
// copy the float into the buffer as astring
sprintf(szBuffer, "%f", size);

MessageBox(NULL, szBuffer, "Size", MB_OK);

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C++

Code:

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#include <sstream>

// this code will not overflow. 
std::stringstream sBuffer;

// insert the float into the buffer
sBuffer << size;
// .str() returns a string, .c_str() returns a const char*
MessageBox(NULL, szBuffer.str().c_str(), "Size", MB_OK);

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clever boost library usage :P
www.boost.org

Code:

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#include <boost/lexical_cast.hpp>
#include <string>

MessageBox(NULL, boost::lexical_cast<std::string>(size).c_str(), "size", MB_OK);

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