C++ strchr() function

As per the name of the function goes, strchr() function is one of the string handling library functions. The function strchr() is used to search for a particular char value in the target string(stored in a c-style char array). Both the char value and string is passed to this function. Let' see the signature of this function.

Signature of strchr()

char *strchr(const char *str, int c)

Looking at the signature of strchr() function, it is passed two parameters when it is called, where -

str - this is a string to be searched is passed to this function.
c - this is a char value to be searched in the string.

Example of strchr() function

char

string

strchr()

char

string

after(including)

// Program to find a character in a String and return remaining string after it.


#include<iostream>
#include<cstring>

using namespace std;

int main()
{
char arr[] = "www.decodejava.com";
char ch = 'j';

char *p = strchr(arr,ch); 	//it prints the string after the searched char value
 
cout<<"String to be searched for a value : "<< arr << "\n";
cout<<"char value to be searched in String : " << ch << "\n";
cout<<"Result of search : "<< p;

return 0;
}

Output is :

String to be searched for a value : www.decodejava.com
char value to be searched in String : j
Result of search : java.com

Program Analysis

char

string

www.decodejava.com

strchr()

string

char

java.com

Another example of strchr() function

strchr()

char

string

does not exist

// Program to find a character at a particular index of a String.


#include<iostream>
#include<cstring>

using namespace std;

int main()
{
char arr[] = "welcome to this site";
char ch = 'k';

char *p = strchr(arr,ch); 
 
cout<< "String to be searched for a value : "<< arr << "\n";
cout<< "char value to be searched in String : " <<  ch << "\n";
cout<< "Result of search : " << p;

return 0;
}

Output is :

String to be searched for a value : welcome to this site
char value to be searched in String : k
Result of search :

Program Analysis

In the code, we have initialized a char array with a string value welcome to this site.
Next on calling function strchr(), we have passed this string value and a char value 'k' to be searched in the string.
On searching, the char value 'k' does not exist in the string, hence strchr() function returns nothing.

Another strchr() function example.

Here in the next code, we are going to use strchr() function to search a string for a char value with multiple occurrences and we will see what happens in this case.

// Program to find a character in a string, with multiple occurrences


#include<iostream>
#include<cstring>

using namespace std;

int main()
{
char arr[] = "a beautiful sky";
char ch = 'e';

char *p = strchr(arr,ch); // it prints the string after the searched char value
 
cout<< "String to be searched for a value : " << arr << "\n";
cout<< "char value to be searched in String : " << ch << "\n";
cout<< "Result of search : " << p;

return 0;
}

Output is :

String to be searched for a value : a beautiful sky
char value to be searched in String : e
Result of search : eautiful sky

Program Analysis

In the code, we have initialized a char array with a string value a beautiful sky.
Next on calling function strchr(), we have passed this string value and a char value 'i' to be searched in the string.
There are two occurrences of char value 'u' in the searched string. hence on searching, the strchr() returns the string, containing the first occurrence of the char value until it's end i.e..utiful sky.