basic_ostringstream Class
The latest version of this topic can be found at basic_ostringstream Class.
Describes an object that controls insertion of elements and encoded objects into a stream buffer of class basic_stringbuf< Elem, Tr, Alloc>.
Syntax
template <class Elem, class Tr = char_traits<Elem>, class Alloc = allocator<Elem>>
class basic_ostringstream : public basic_ostream<Elem, Tr>
Parameters
Alloc
The allocator class.
Elem
The type of the basic element of the string.
Tr
The character traits specialized on the basic element of the string.
Remarks
The class describes an object that controls insertion of elements and encoded objects into a stream buffer, with elements of type Elem, whose character traits are determined by the class Tr, and whose elements are allocated by an allocator of class Alloc. The object stores an object of class basic_stringbuf< Elem, Tr, Alloc>.
Constructors
| basic_ostringstream | Constructs an object of type basic_ostringstream. |
Typedefs
| allocator_type | The type is a synonym for the template parameter Alloc. |
Member Functions
| rdbuf | Returns the address of the stored stream buffer of type pointer to basic_stringbuf< Elem, Tr, Alloc>. |
| str | Sets or gets the text in a string buffer without changing the write position. |
Requirements
Header: <sstream>
Namespace: std
basic_ostringstream::allocator_type
The type is a synonym for the template parameter Alloc.
typedef Alloc allocator_type;
basic_ostringstream::basic_ostringstream
Constructs an object of type basic_ostringstream.
explicit basic_ostringstream(ios_base::openmode _Mode = ios_base::out);
explicit basic_ostringstream(const basic_string<Elem, Tr, Alloc>& str, ios_base::openmode _Mode = ios_base::out);
Parameters
_Mode
One of the enumerations in ios_base::openmode.
str
An object of type basic_string.
Remarks
The first constructor initializes the base class by calling basic_ostream( sb), where sb is the stored object of class basic_stringbuf< Elem, Tr, Alloc>. It also initializes sb by calling basic_stringbuf< Elem, Tr, Alloc>( _Mode | ios_base::out).
The second constructor initializes the base class by calling basic_ostream( sb). It also initializes sb by calling basic_stringbuf< Elem, Tr, Alloc>(_ Str, _Mode | ios_base::out).
basic_ostringstream::rdbuf
Returns the address of the stored stream buffer of type pointer to basic_stringbuf< Elem, Tr, Alloc>.
basic_stringbuf<Elem, Tr, Alloc> *rdbuf() const;
Return Value
The address of the stored stream buffer, of type pointer to basic_stringbuf< Elem, Tr, Alloc>.
Remarks
The member function returns the address of the stored stream buffer of type pointer to basic_stringbuf< Elem, Tr, Alloc>.
Example
See basic_filebuf::close for an example that uses rdbuf.
basic_ostringstream::str
Sets or gets the text in a string buffer without changing the write position.
basic_string<Elem, Tr, Alloc> str() const;
void str(
const basic_string<Elem, Tr, Alloc>& _Newstr);
Parameters
_Newstr
The new string.
Return Value
Returns an object of class basic_string< Elem, Tr, Alloc>, whose controlled sequence is a copy of the sequence controlled by *this.
Remarks
The first member function returns rdbuf -> str. The second member function calls rdbuf -> str( _Newstr).
Example
See basic_stringbuf::str for an example that uses str.
See Also
Thread Safety in the C++ Standard Library
iostream Programming
iostreams Conventions