What is the C++ equivalent of sprintf?

The sprintf() function of C library equivalent to C++ that is used to create strings with a specified format like custom text with numbers or names. In C++, we can perform the same operation as in C with the help of ostringstream.

C++ std::ostringstream

The ostringstream is known for the output string stream and is defined under <sstream> header file. This is used to build the string by writing some text into it.

Syntax

i. Following is the basic syntax of sprint() function in C:

int sprintf(char *str, const char *format, ...);

ii. Here, we show the syntax of C++ function which has similar function w.r.t sprintf():

ostringstream os;

Example of C++ Equivalent to sprint() Function

In this program, we shows how ostringstream of C++ works similar to the sprintf() of C. Here, we write one program line as os << "This is a string... which demonstrates how to add text and numbers into the stream.

#include<iostream>
#include<sstream>
using namespace std;

int main() {
   string my_str;
   
   // os is just name of the variable
   ostringstream os;
   
   os << "This is a string where we will store the value of " << 50 << " and also store the value as " << 52.32 ;
   
   // convert stream to my_str string
   my_str = os.str(); 
   cout << my_str;
   return 0;
}

The above code produces the following output:

This is a string where we will store the value of 50 and also store the value as 52.32