NAME¶

std::istrstream::istrstream - std::istrstream::istrstream

Synopsis¶

explicit istrstream(const char* s); (1)
explicit istrstream(char* s); (2)
istrstream(const char* s, std::streamsize n); (3)
istrstream(char* s, std::streamsize n); (4)

Constructs new istrstream and its underlying std::strstreambuf.

1,2) Constructs the underlying std::strstreambuf by calling strstreambuf(s,0) and
initializes the base class with the address of the strstreambuf. The behavior is
undefined if s is not pointing at an element of a null-terminated array.
3,4) Constructs the underlying std::strstreambuf by calling strstreambuf(s,n) and
initializes the base class with the address of the strstreambuf. The behavior is
undefined if s is not pointing at an element of an array whose length is at least n
elements.

Parameters¶

s - C-string or char array to use as the contents of the stream
n - size of the array

Example¶

// Run this code

#include <iostream>
#include <strstream>

int main()
{
std::istrstream s1("1 2 3"); // string literal
int n1,n2,n3;
if(s1 >> n1 >> n2 >> n3)
std::cout << n1 << ", " << n2 << ", " << n3 << '\n';

char arr[] = {'4', ' ', '5', ' ', '6'};
std::istrstream s2(arr, sizeof arr);
if(s2 >> n1 >> n2 >> n3)
std::cout << n1 << ", " << n2 << ", " << n3 << '\n';
}

Output:¶

1, 2, 3
4, 5, 6

See also¶

constructor constructs a strstreambuf object
(public member function of std::strstreambuf)
constructor constructs an strstream, optionally allocating the buffer
(public member function of std::ostrstream)
constructor constructs an strstream, optionally allocating the buffer
(public member function of std::strstream)