C++ String Library - substr

---

Description

It returns a newly constructed string object with its value initialized to a copy of a substring of this object.

Declaration

Following is the declaration for std::string::substr.

string substr (size_t pos = 0, size_t len = npos) const;

C++11

string substr (size_t pos = 0, size_t len = npos) const;

C++14

string substr (size_t pos = 0, size_t len = npos) const;

Parameters

• str − It is a string object.

• len − It is used to copy the characters.

• pos − Position of the first character to be copied.

Return Value

It returns a string object with a substring of this object.

Exceptions

if an exception is thrown, there are no changes in the string.

Example

In below example for std::string::substr.

#include <iostream>
#include <string>

int main () {
   std::string str="Tutorialspoit is a one the best site in the world, hope so it will move same .";

   std::string str2 = str.substr (3,5);

   std::size_t pos = str.find("live");

   std::string str3 = str.substr (pos);

   std::cout << str2 << ' ' << str3 << '\n';

   return 0;
}

The sample output should be like this −

Hello, 1!