basic_istringstream

Overview

basic_istringstream are designed to receive inputs from sources such as strings.

Details

The class template basic_istringstream provides support for high level input operations on character streams based on strings. The supported operations include formatted input (e.g. integer values or whitespace-separated characters and characters strings) and unformatted input (e.g. raw characters and character arrays). 

Syntax

template<class CharT, class Traits = char_traits<CharT>, class Alloc = allocator<charT>> 
class basic_istringstream: public basic_istream<CharT,Traits> 

where CharT can be char or wchar_t. It's derived from basic_istream class.

member types

Following properties are defined.

Name	Definition
char_type	char,wchar_t
traits_type	char_traits<char_type>
allocator_type	Allocator<char_type>
int_type	char_traits<char_type>::int_type
pos_type	char_traits<char_type>::pos_type
off_type	char_traits<char_type>::off_type

openmode➹

The openmode flags indicate how the streams such as disk files or memory streams can be opened for IO operations such as read, write or append.

Constructor

Name	Description
basic_istringstream (ios_base::openmode mode = ios_base::in) basic_istringstream (const basic_string& s, ios_base::openmode mode = ios_base::in)	Constructs an empty basic_istringstream object. Constructs basic_istringstream object with the content from s. The mode constants are defined in ios_base class. Example istringstream s, s2 {"hello, world!"};

Methods

Name
Description
basic_streambuf* rdbuf()
Returns pointer to the underlying raw file device object.

Example
istringstream s {"hello, world!"};
auto sb = s.rdbuf();
void str
(const basic_string& s) 
basic_string str()
Sets the current contents of the stream to s
Returns the current contents of the stream as string.
Example
istringstream ss,ss2;
ss.str("hello, world!");
ss2.str(ss.str());