Re: "Type-safe" sprintf
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Try this instead (much cleaner - see examples below):
#include <string>
#include <sstream>
#include <tchar.h>
// TCHAR versions of "std::string", etc.
typedef std::basic_string<TCHAR> tstring;
typedef std::basic_ostringstream<TCHAR> tostringstream;
/////////////////////////////////////////////////////////////////////////=
////
// "FormatStr" class. Use this class to format a "tstring" on the fly =
with
// streaming arguments. It's basically the C++ answer to "sprintf()" =
style
// argument lists. Instead of passing a format string and variable =
number
// of arguments however, just construct a temporary as seen in the =
examples
// below and stream the same arguments you would normally pass to any
// "std::ostream" object via the << operator. The result can then be
// implicitly converted to a "tstring" via the "tstring()" operator so
// you can effectively use it wherever you would use a "tstring" =
(frequently
// as a "const tstring &" argument for instance - see example 2 below).
//
// Example 1
// ---------
//
// // Results in "Bill Gates is worth 50 billion dollars"
// tstring String = FormatStr() << _T("Bill Gates is worth ") << 50 =
<< _T(" billion dollars");
//
// Example 2 (as above but pass to a function on the fly)
// ---------
//
// void YourFunc(const tstring &String)
// {
// // ...
// }
//
// YourFunc(FormatStr() << _T("Bill Gates is worth ") << 50 << _T(" =
billion dollars");
//
/////////////////////////////////////////////////////////////////////////=
////
class FormatStr
{
public:
////////////////////////////////////////////
// IMPORTANT: Don't make T a reference arg
// under VC6 (unfortunately). Some later
// versions of VC6 have a bug and will
// choke on it (infamous "internal compiler"
// error).
////////////////////////////////////////////
template <typename T>
FormatStr &operator<<(const T &Whatever)
{
m_Stream << Whatever;
return *this;
}
operator tstring() const
{
return m_Stream.str();
}
private:
tostringstream m_Stream;
};
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<DIV><FONT face="Courier New" size=2>Try this instead =
(much cleaner - see
examples below):</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>#include =
<string><BR>#include
<sstream><BR>#include <tchar.h></FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>// TCHAR versions of =
"std::string",
etc.<BR>typedef std::basic_string<TCHAR> tstring;<BR>typedef
std::basic_ostringstream<TCHAR> tostringstream;</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New"
size=2>////////////////////////////////////////////////////////////////=
/////////////<BR>//
"FormatStr" class. Use this class to format a "tstring" on the fly =
with<BR>//
streaming arguments. It's basically the C++ answer to "sprintf()" =
style<BR>//
argument lists. Instead of passing a format string and variable =
number<BR>// of
arguments however, just construct a temporary as seen in the =
examples<BR>//
below and stream the same arguments you would normally pass to any<BR>// =
"std::ostream" object via the << operator. The result can then =
be<BR>//
implicitly converted to a "tstring" via the "tstring()" operator =
so<BR>// you
can effectively use it wherever you would use a "tstring" =
(frequently<BR>// as a
"const tstring &" argument for instance - see example 2 =
below).<BR>//<BR>//
Example 1<BR>// ---------<BR>//<BR>// // Results in "Bill =
Gates is
worth 50 billion dollars"<BR>// tstring String = =
FormatStr()
<< _T("Bill Gates is worth ") << 50 << _T(" billion
dollars");<BR>//<BR>// Example 2 (as above but pass to a function on the =
fly)<BR>// ---------<BR>//<BR>// void YourFunc(const tstring =
&String)<BR>// =
{<BR>// //
....<BR>// }<BR>//<BR>// YourFunc(FormatStr() =
<<
_T("Bill Gates is worth ") << 50 << _T(" billion
dollars");<BR>//<BR>/////////////////////////////////////////////////////=
////////////////////////<BR>class
FormatStr<BR>{<BR>public:<BR>
////////////////////////////////////////////<BR> // =
IMPORTANT:
Don't make T a reference arg<BR> // under VC6 =
(unfortunately).
Some later<BR> // versions of VC6 have a bug and
will<BR> // choke on it (infamous "internal
compiler"<BR> // error).<BR>
////////////////////////////////////////////<BR> =
template
<typename T><BR> FormatStr =
&operator<<(const T
&Whatever)<BR>
{<BR> m_Stream <<
Whatever;<BR> return
*this;<BR> }</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2> operator =
tstring()
const<BR> =
{<BR>
return m_Stream.str();<BR> }</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>private:<BR>
tostringstream m_Stream;<BR>};</FONT></DIV></BODY></HTML>
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