Visual Studio - How can I output debug information to debug window?

Question

OutputDebugString method seems rather tedious and seems only limited to string and not polymorphic. What should I do if I want to output some integer or other variable type ?

Hope some function like std::cout exists !

Answer 1

I'm pretty sure you could write a streambuf implementation that outputs via OutputDebugString. It's not entirely straight forward, but possible.

It would certainly be possible to use something like this:

std::stringstream ss;
ss << something << another << variable << here << endl;
OutputDebugString(ss.str().c_str()); 

You may need to use MultiByteToWideChar to convert the c_str() to a wide string, if you have "UNICODE" enabled in your project.

Answer 2

Since the accepted answer doesn't really provide a working version:

If you're not concerned with unicode - though you probably should be if you're shipping anything, I'll assume you won't be shipping it with OutputDebugString included - you can use one of the other versions, such as OutputDebugStringA:

stringstream ss;

ss << "Hello World\n";

OutputDebugStringA(ss.str().c_str());

Answer 3

Use a class like this:

class stringbuilder
{
public:
  stringbuilder()
  {
  }

  template< class T >
  stringbuilder& operator << ( const T& val )
  {
    os << val;
    return *this;
  }

  operator std::string () const
  {
    return os.str();
  }

private:
  std::ostringstream os;
};

And pass the output to a wrapper around OutputDebugString (or anything else that logs strings only):

void MyOutputDebugString( const std::string& s )
{
  ::OutputDebugString( s.c_str() );
}

  //usage:
MyOutputDebugString( stringbuilder() << "integer " << 5 );

Answer 4

A macro for Mats Petersson's answer, with unicode support:

#define odslog(msg) { std::wstringstream ss; ss << msg; OutputDebugStringW(ss.str().c_str()); }

Usage:

odslog("A string " << 123123 << L"A wide string" << "\n");