The basic_string::c_str() is a built-in function in C++ which returns a pointer to an array that contains a null-terminated sequence of characters representing the current value of the basic_string object. This array includes the same sequence of characters that make up the value of the basic_string object plus an additional terminating null-character at the end.
Syntax:
const CharT* c_str() const
Parameter: The function does not accept any parameter.
Return Value : The function returns a constant Null terminated pointer to the character array storage of the string.
Below is the implementation of the above function:
Program 1:
// C++ code for illustration of // basic_string::c_str function #include <bits/stdc++.h> #include <string> using namespace std;
int main()
{ // declare a example string
string s1 = "GeeksForGeeks" ;
// check if the size of the string is same as the
// size of character pointer given by c_str
if (s1.size() == strlen (s1.c_str())) {
cout << "s1.size is equal to strlen(s1.c_str()) " << endl;
}
else {
cout << "s1.size is not equal to strlen(s1.c_str())" << endl;
}
// print the string
printf ( "%s \n" , s1.c_str());
} |
s1.size is equal to strlen(s1.c_str()) GeeksForGeeks
Program 2:
// C++ code for illustration of // basic_string::c_str function #include <bits/stdc++.h> #include <string> using namespace std;
int main()
{ // declare a example string
string s1 = "Aditya" ;
// print the characters of the string
for ( int i = 0; i < s1.length(); i++) {
cout << "The " << i + 1 << "th character of string " << s1
<< " is " << s1.c_str()[i] << endl;
}
} |
The 1th character of string Aditya is A The 2th character of string Aditya is d The 3th character of string Aditya is i The 4th character of string Aditya is t The 5th character of string Aditya is y The 6th character of string Aditya is a
Program 3:
// CPP program to copy the string // using std::string::c_str() method #include <bits/stdc++.h> // Function to copy the string const char * copyString(std::string s)
{ const char * s2;
// std::string::c_str() method
s2 = s.c_str();
return s2;
} // Driver Code int main()
{ std::string s1 = "GeeksforGeeks" ;
std::string s2;
// Function Call
s2 = copyString(s1);
std::cout << s2;
return 0;
} // This code is contributed by Susobhan Akhuli |
GeeksforGeeks