[ostringstream.general]

# 31 Input/output library [[input.output]](./#input.output)

## 31.8 String-based streams [[string.streams]](string.streams#ostringstream.general)

### 31.8.4 Class template basic_ostringstream [[ostringstream]](ostringstream#general)

#### 31.8.4.1 General [ostringstream.general]

[🔗](#lib:basic_ostringstream)

namespace std {template<class charT, class traits = char_traits<charT>, class Allocator = allocator<charT>>class basic_ostringstream : 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; using allocator_type = Allocator; // [[ostringstream.cons]](ostringstream.cons "31.8.4.2 Constructors"), constructors basic_ostringstream() : basic_ostringstream(ios_base::out) {}explicit basic_ostringstream(ios_base::openmode which); explicit basic_ostringstream(const basic_string<charT, traits, Allocator>& s,
 ios_base::openmode which = ios_base::out);
 basic_ostringstream(ios_base::openmode which, const Allocator& a); explicit basic_ostringstream( basic_string<charT, traits, Allocator>&& s,
 ios_base::openmode which = ios_base::out); template<class SAlloc> basic_ostringstream(const basic_string<charT, traits, SAlloc>& s, const Allocator& a): basic_ostringstream(s, ios_base::out, a) {}template<class SAlloc> basic_ostringstream(const basic_string<charT, traits, SAlloc>& s,
 ios_base::openmode which, const Allocator& a); template<class SAlloc>explicit basic_ostringstream(const basic_string<charT, traits, SAlloc>& s,
 ios_base::openmode which = ios_base::out); template<class T>explicit basic_ostringstream(const T& t, ios_base::openmode which = ios_base::out); template<class T> basic_ostringstream(const T& t, const Allocator& a); template<class T> basic_ostringstream(const T& t, ios_base::openmode which, const Allocator& a);
 basic_ostringstream(const basic_ostringstream&) = delete;
 basic_ostringstream(basic_ostringstream&& rhs);

 basic_ostringstream& operator=(const basic_ostringstream&) = delete;
 basic_ostringstream& operator=(basic_ostringstream&& rhs); // [[ostringstream.swap]](ostringstream.swap "31.8.4.3 Swap"), swapvoid swap(basic_ostringstream& rhs); // [[ostringstream.members]](ostringstream.members "31.8.4.4 Member functions"), members basic_stringbuf<charT, traits, Allocator>* rdbuf() const;

 basic_string<charT, traits, Allocator> str() const &; template<class SAlloc> basic_string<charT,traits,SAlloc> str(const SAlloc& sa) const;
 basic_string<charT, traits, Allocator> str() &&;
 basic_string_view<charT, traits> view() const noexcept; void str(const basic_string<charT, traits, Allocator>& s); template<class SAlloc>void str(const basic_string<charT, traits, SAlloc>& s); void str(basic_string<charT, traits, Allocator>&& s); template<class T>void str(const T& t); private: basic_stringbuf<charT, traits, Allocator> *sb*; // *exposition only*};}

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iostreams.tex#L9325)

The classbasic_ostringstream<charT, traits, Allocator> supports writing objects of classbasic_string<​charT, traits, Allocator>[.](#1.sentence-1)

It uses abasic_stringbuf object to control the associated storage[.](#1.sentence-2)

For the sake of exposition, the maintained data is presented here as:

- [(1.1)](#1.1)

*sb*, the stringbuf object[.](#1.sentence-3)