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basic_string::substr

Copies a substring of at most some number of characters from a string beginning from a specified position.

basic_string<CharType, Traits, Allocator> substr(
     size_type _Off = 0,
     size_type _Count = npos
) const;

Parameters

  • _Off
    An index locating the element at the position from which the copy of the string is made, with a default value of 0.

  • _Count
    The number of characters that are to be copied if they are present.

Return Value

A substring object that is a copy of elements of the string operand beginning at the position specified by the first argument.

Example

// basic_string_substr.cpp
// compile with: /EHsc
#include <string>
#include <iostream>

int main( ) 
{
   using namespace std;

   string  str1 ("Heterological paradoxes are persistent.");
   cout << "The original string str1 is: \n " << str1
        << endl << endl;

   basic_string <char> str2 = str1.substr ( 6 , 7 );
   cout << "The substring str1 copied is: " << str2
        << endl << endl;
   
   basic_string <char> str3 = str1.substr (  );
   cout << "The default substring str3 is: \n " << str3
        <<  "\n which is the entire original string." << endl;
}

The original string str1 is: 
 Heterological paradoxes are persistent.

The substring str1 copied is: logical

The default substring str3 is: 
 Heterological paradoxes are persistent.
 which is the entire original string.

Requirements

Header: <string>

Namespace: std

See Also

Concepts

basic_string Class

basic_string Members