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Standard library header <fstream>

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C++
Standard library headers

此头文件是 输入/输出 库的组成部分。

目录

类

实现原始文件设备
(类模板)
实现高级文件流输入操作
(类模板)
实现高级文件流输出操作
(类模板)
实现高级文件流输入/输出操作
(类模板)
filebuf std:: basic_filebuf < char >
(类型定义)
wfilebuf std:: basic_filebuf < wchar_t >
(类型定义)
ifstream std:: basic_ifstream < char >
(类型定义)
wifstream std:: basic_ifstream < wchar_t >
(类型定义)
ofstream std:: basic_ofstream < char >
(类型定义)
wofstream std:: basic_ofstream < wchar_t >
(类型定义)
fstream std:: basic_fstream < char >
(类型定义)
wfstream std:: basic_fstream < wchar_t >
(类型定义)

函数

(C++11)
特化 std::swap 算法
(函数模板)
(C++11)
特化 std::swap 算法
(函数模板)
(C++11)
特化 std::swap 算法
(函数模板)
(C++11)
特化 std::swap 算法
(函数模板)

概要 

namespace std {
  template<class CharT, class Traits = char_traits<CharT>>
    class basic_filebuf;
  using filebuf  = basic_filebuf<char>;
  using wfilebuf = basic_filebuf<wchar_t>;
  template<class CharT, class Traits = char_traits<CharT>>
    class basic_ifstream;
  using ifstream  = basic_ifstream<char>;
  using wifstream = basic_ifstream<wchar_t>;
  template<class CharT, class Traits = char_traits<CharT>>
    class basic_ofstream;
  using ofstream  = basic_ofstream<char>;
  using wofstream = basic_ofstream<wchar_t>;
  template<class CharT, class Traits = char_traits<CharT>>
    class basic_fstream;
  using fstream  = basic_fstream<char>;
  using wfstream = basic_fstream<wchar_t>;
}
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类模板 std::basic_filebuf 

namespace std {
  template<class CharT, class Traits = char_traits<CharT>>
  class basic_filebuf : public basic_streambuf<CharT, Traits> {
  public:
    using char_type   = CharT;
    using int_type    = typename Traits::int_type;
    using pos_type    = typename Traits::pos_type;
    using off_type    = typename Traits::off_type;
    using traits_type = Traits;
    // 构造函数/析构函数
    basic_filebuf();
    basic_filebuf(const basic_filebuf&) = delete;
    basic_filebuf(basic_filebuf&& rhs);
    virtual ~basic_filebuf();
    // 赋值与交换
    basic_filebuf& operator=(const basic_filebuf&) = delete;
    basic_filebuf& operator=(basic_filebuf&& rhs);
    void swap(basic_filebuf& rhs);
    // 成员函数
    bool is_open() const;
    basic_filebuf* open(const char* s, ios_base::openmode mode);
    basic_filebuf* open(const filesystem::path::value_type* s,
                        ios_base::openmode mode);   // 仅宽字符系统
    basic_filebuf* open(const string& s,
                        ios_base::openmode mode);
    basic_filebuf* open(const filesystem::path& s,
                        ios_base::openmode mode);
    basic_filebuf* close();
  protected:
    // 重写的虚函数
    streamsize showmanyc() override;
    int_type underflow() override;
    int_type uflow() override;
    int_type pbackfail(int_type c = Traits::eof()) override;
    int_type overflow (int_type c = Traits::eof()) override;
    basic_streambuf<CharT, Traits>* setbuf(char_type* s,
                                           streamsize n) override;
    pos_type seekoff(off_type off, ios_base::seekdir way,
                     ios_base::openmode which
                      = ios_base::in | ios_base::out) override;
    pos_type seekpos(pos_type sp,
                     ios_base::openmode which
                      = ios_base::in | ios_base::out) override;
    int      sync() override;
    void     imbue(const locale& loc) override;
  };
  template<class CharT, class Traits>
    void swap(basic_filebuf<CharT, Traits>& x,
              basic_filebuf<CharT, Traits>& y);
}

类模板 std::basic_ifstream 

namespace std {
  template<class CharT, class Traits = char_traits<CharT>>
  class basic_ifstream : public basic_istream<CharT, Traits> {
  public:
    using char_type   = CharT;
    using int_type    = typename Traits::int_type;
    using pos_type    = typename Traits::pos_type;
    using off_type    = typename Traits::off_type;
    using traits_type = Traits;
    // 构造函数
    basic_ifstream();
    explicit basic_ifstream(const char* s,
                            ios_base::openmode mode = ios_base::in);
    explicit basic_ifstream(const filesystem::path::value_type* s,
                            ios_base::openmode mode = ios_base::in);// 仅宽字符系统
    explicit basic_ifstream(const string& s,
                            ios_base::openmode mode = ios_base::in);
    explicit basic_ifstream(const filesystem::path& s,
                            ios_base::openmode mode = ios_base::in);
    basic_ifstream(const basic_ifstream&) = delete;
    basic_ifstream(basic_ifstream&& rhs);
    // 赋值与交换
    basic_ifstream& operator=(const basic_ifstream&) = delete;
    basic_ifstream& operator=(basic_ifstream&& rhs);
    void swap(basic_ifstream& rhs);
    // 成员函数
    basic_filebuf<CharT, Traits>* rdbuf() const;
    bool is_open() const;
    void open(const char* s, ios_base::openmode mode = ios_base::in);
    void open(const filesystem::path::value_type* s,
              ios_base::openmode mode = ios_base::in);  // 仅宽字符系统
    void open(const string& s, ios_base::openmode mode = ios_base::in);
    void open(const filesystem::path& s, ios_base::openmode mode = ios_base::in);
    void close();
  private:
    basic_filebuf<CharT, Traits> sb;    // 仅用于说明
  };
  template<class CharT, class Traits>
    void swap(basic_ifstream<CharT, Traits>& x,
              basic_ifstream<CharT, Traits>& y);
}

类模板 std::basic_ofstream 

namespace std {
  template<class CharT, class Traits = char_traits<CharT>>
  class basic_ofstream : public basic_ostream<CharT, Traits> {
  public:
    using char_type   = CharT;
    using int_type    = typename Traits::int_type;
    using pos_type    = typename Traits::pos_type;
    using off_type    = typename Traits::off_type;
    using traits_type = Traits;
    // 构造函数
    basic_ofstream();
    explicit basic_ofstream(const char* s,
                            ios_base::openmode mode = ios_base::out);
    explicit basic_ofstream(const filesystem::path::value_type* s,  // 仅宽字符系统
                            ios_base::openmode mode = ios_base::out);
    explicit basic_ofstream(const string& s,
                            ios_base::openmode mode = ios_base::out);
    explicit basic_ofstream(const filesystem::path& s,
                            ios_base::openmode mode = ios_base::out);
    basic_ofstream(const basic_ofstream&) = delete;
    basic_ofstream(basic_ofstream&& rhs);
    // 赋值与交换
    basic_ofstream& operator=(const basic_ofstream&) = delete;
    basic_ofstream& operator=(basic_ofstream&& rhs);
    void swap(basic_ofstream& rhs);
    // 成员函数
    basic_filebuf<CharT, Traits>* rdbuf() const;
    bool is_open() const;
    void open(const char* s, ios_base::openmode mode = ios_base::out);
    void open(const filesystem::path::value_type* s,
              ios_base::openmode mode = ios_base::out);     // 仅宽字符系统
    void open(const string& s, ios_base::openmode mode = ios_base::out);
    void open(const filesystem::path& s, ios_base::openmode mode = ios_base::out);
    void close();
  private:
    basic_filebuf<CharT, Traits> sb;    // 仅用于说明
  };
  template<class CharT, class Traits>
    void swap(basic_ofstream<CharT, Traits>& x,
              basic_ofstream<CharT, Traits>& y);
}

类模板 std::basic_fstream 

namespace std {
  template<class CharT, class Traits = char_traits<CharT>>
  class basic_fstream : public basic_iostream<CharT, Traits> {
  public:
    using char_type   = CharT;
    using int_type    = typename Traits::int_type;
    using pos_type    = typename Traits::pos_type;
    using off_type    = typename Traits::off_type;
    using traits_type = Traits;
    // 构造函数
    basic_fstream();
    explicit basic_fstream(
      const char* s,
      ios_base::openmode mode = ios_base::in | ios_base::out);
    explicit basic_fstream(
      const filesystem::path::value_type* s,
      ios_base::openmode mode = ios_base::in | ios_base::out);    // 仅宽字符系统
    explicit basic_fstream(
      const string& s,
      ios_base::openmode mode = ios_base::in | ios_base::out);
    explicit basic_fstream(
      const filesystem::path& s,
      ios_base::openmode mode = ios_base::in | ios_base::out);
    basic_fstream(const basic_fstream&) = delete;
    basic_fstream(basic_fstream&& rhs);
    // 赋值与交换
    basic_fstream& operator=(const basic_fstream&) = delete;
    basic_fstream& operator=(basic_fstream&& rhs);
    void swap(basic_fstream& rhs);
    // 成员函数
    basic_filebuf<CharT, Traits>* rdbuf() const;
    bool is_open() const;
    void open(
      const char* s,
      ios_base::openmode mode = ios_base::in | ios_base::out);
    void open(
      const filesystem::path::value_type* s,
      ios_base::openmode mode = ios_base::in | ios_base::out);    // 仅宽字符系统
    void open(
      const string& s,
      ios_base::openmode mode = ios_base::in | ios_base::out);
    void open(
      const filesystem::path& s,
      ios_base::openmode mode = ios_base::in | ios_base::out);
    void close();
  private:
    basic_filebuf<CharT, Traits> sb;    // 仅用于说明
  };
  template<class CharT, class Traits>
    void swap(basic_fstream<CharT, Traits>& x,
              basic_fstream<CharT, Traits>& y);
}