Open In App
Related Articles

PHP strpos() and stripos() Functions

Improve
Improve
Improve
Like Article
Like
Save Article
Save
Report issue
Report

In this article, we will see how to find the position of the first occurrence of a string in another string using strpos() and stripos() Functions in PHP, & will see their implementation through the examples.

Both the strpos() and stripos() Functions in PHP are binary-safe which means the function will handle its input as a raw byte stream and disregard every textual content it may contain. Here, the function will work correctly while passing arbitrary binary data ie., a string having non-ASCII bytes &/or null-bytes.

strpos() Function: This function helps us to find the position of the first occurrence of a string in another string. This returns an integer value of the position of the first occurrence of the string. This function is case-sensitive, which means that it treats upper-case and lower-case characters differently.

Syntax: 

strpos(original_str, search_str, start_pos);

Parameter value: Out of the three parameters specified in the syntax, two are mandatory and one is optional. The three parameters are described below:

  • original_str: This is a mandatory parameter that refers to the original string in which we need to search the occurrence of the required string.
  • search_str: This is a mandatory parameter that refers to the string that we need to search.
  • start_pos: This is an optional parameter that refers to the position of the string from where the search must begin.

Return Type: This function returns an integer value that represents the index of original_str where the string search_str first occurs.

Example: This example illustrates the strpos() function that specifies the position of the occurrence of a string in another string.

PHP

<?php
 
    // PHP code to search for a specific string's position
    // first occurrence using strpos() case-sensitive function
    function Search($search, $string)
    {
        $position = strpos($string, $search, 5);
        if (is_numeric($position))
        {
            return "Found at position: " . $position;
        }
        else
        {
            return "Not Found";
        }
    }
     
    // Driver Code
    $string = "Welcome to GeeksforGeeks";
    $search = "Geeks";
    echo Search($search, $string);
?>

                    

Output:

Found at position 11

stripos() Function: This function also helps us to find the position of the first occurrence of a string in another string. This returns an integer value of the position of the first occurrence of the string. This function is case-insensitive, which means it treats both upper-case and lower-case characters equally. This function works similarly as strpos(), the difference is that it is case in-sensitive whereas strpos() is case sensitive.

Syntax:  

stripos(original_str, search_str, start_pos);

Parameter value: Out of the three parameters specified in the syntax, two are mandatory and one is optional.

  • original_str: This is a mandatory parameter that refers to the original string in which we need to search the occurrence of the required string.
  • search_str: This is a mandatory parameter that refers to the string that we need to find.
  • start_pos: This is an optional parameter that refers to the position of the string from where the search must begin.

Return Type: This function returns an integer value that represents the index of original_str where the string search_str first occurs.

Example: This example illustrates the stripos() function that specifies the position of the occurrence of a string in another string.

PHP

<?php
 
    // PHP code to search for a specific string
    // first occurrence using stripos() case-insensitive function
    function Search($search, $string)
    {
        $position = stripos($string, $search, 5);
        if ($position == true)
        {
            return "Found at position " . $position;
        }
        else
        {
            return "Not Found";
        }
    }
     
    // Driver Code
    $string = "Welcome to GeeksforGeeks";
    $search = "geeks";
    echo Search($search, $string);
?>

                    

Output: 

Found at position 11

Let us understand these functions in a tabular form -:

 strpos()stripos() 
1.The strpos() function finds the position of the first occurrence of a string inside another string.The stripos() function finds the position of the first occurrence of a string inside another string.
2.It is case-sensitive function.It is case-insensitive function.
3.

Its syntax is -:

strpos(string,find,start)

Its syntax is -:

stripos(string,find,start)

4.This function returns the position of the first occurrence of a string inside another string else it returns false if the string does not found.It returns the position of the first occurrence of a string inside another string else it returns false if the string does not found.
5.It is supported in PHP version 4.0+It is supported in PHP version 5.0+


Last Updated : 09 May, 2022
Like Article
Save Article
Previous
Next
Share your thoughts in the comments
Similar Reads