qdebugstream.h

QT4的utils库源码包.解压后运行./configure配置,然后make.使用时在.pro文件中加入两行:LIBS+=-L$$(CPPLIBS)-lutils及INCLUDEPATH+=$$(C

#ifndef Q_DEBUGSTREAM_H
#define Q_DEBUGSTREAM_H
#include "myexport.h"
#include <iostream>
#include <streambuf>
#include <string>
#include <qglobal.h>

/**
    A convenience class for wrapping the standard iostreams into
    objects, which will send the output to qdebug.
 
   It is faster, of course, to write directly to qDebug, but if you
   have existing code that uses iostream and want a cheap way of redirecting,
   this is it.
 
   Usage:
   QApplication app(argc, argv);
 
   // these redirect both cout/cerr
   QDebugStream qdsOut(std::cout);
   QDebugStream qdsErr(std::cerr);
   
   // now start using cout and cerr normally
   std::cerr << "Oops";   // this goes to your QDebug handler
 
   Original idea came from here:
        http://www.qtforum.org/thread.php?threadid=678  
 
*/

class UTILS_EXPORT QDebugStream : public std::basic_streambuf<char> {
public:
    QDebugStream(std::ostream &stream);
    ~QDebugStream();

protected:
    virtual int_type overflow(int_type v);
    virtual std::streamsize xsputn(const char *p, std::streamsize n);

private:
    std::ostream &m_Stream;
    std::streambuf *m_OldBuf;
    std::string m_String;
};

#endif