Re: How to use std::cout to output a char as a number?

From:

dan.furlani@earthling.net

Newsgroups:

comp.lang.c++

Date:

Mon, 01 Oct 2007 16:32:52 -0700

Message-ID:

<1191281572.092599.89760@g4g2000hsf.googlegroups.com>

On Apr 30, 7:52 am, Dancefire <Dancef...@gmail.com> wrote:

Hi, everyone

It might be a simple question, but I really don't know the answer.

charc = '1';cout<< c;

The above code will only output a '1' rather than 0x31;

A quick and dirty solution:

  class MyOs {
  public:
    MyOs(ostream &os) : os_(os) { }

    template <typename T>
    ostream & operator<<(T thing) { os_ << thing; return os_; }

    ostream & operator<<(char ch) // treat as unsigned.
    { os_ << static_cast<unsigned short>(static_cast<unsigned
char>(ch)); return os_; }
    ostream & operator<<(signed char ch)
    { os_ << static_cast<signed short>(ch); return os_; }
    ostream & operator<<(unsigned char ch)
    { os_ << static_cast<unsigned short>(ch); return os_; }

  private:
    ostream &os_;
  };

  enum Fix_Char { fix_char };
  MyOs operator<<(ostream &os, Fix_Char f) { return MyOs(os); }

Now you can do this:

  template <typename T>
  void foo(T arg) {
    cout << "test " << fix_char << arg << endl;
  }

I think that does what Dancefire wants but it sure is ugly. Can
someone please suggest the correct way to implement this?

-Dan