PHP | strtoupper() Function

The strtoupper() function is used to convert a string into uppercase. This function takes a string as parameter and converts all the lowercase english alphabets present in the string to uppercase. All other numeric characters or special characters in the string remains unchanged.

Syntax:

string strtoupper ( $string )

Parameter: The only parameter to this function is a string that is to be converted to upper case.

Return value: This function returns a string in which all the alphabets are uppercase.

Examples:



Input : $str  = "GeeksForGeeks"
        strtoupper($str)
Output: GEEKSFORGEEKS

Input : $str  = "going BACK he SAW THIS 123$#%"
        strtoupper($str)
Output: GOING BACK HE SAW THIS 123$#%

Below programs illustrate the strtoupper() function in PHP:

Program 1

filter_none

edit
close

play_arrow

link
brightness_4
code

<?php
  
// original string
$str = "GeeksForGeeks";
  
// string converted to upper case
$resStr = strtoupper($str);
  
print_r($resStr);
  
?>

chevron_right


Output:

GEEKSFORGEEKS

Program 2

filter_none

edit
close

play_arrow

link
brightness_4
code

<?php
  
// original string
$str = "going BACK he SAW THIS 123$#%";
  
// string to upper case
$resStr = strtoupper($str);
  
print_r($resStr);
  
?>

chevron_right


Output:

GOING BACK HE SAW THIS 123$#%

Reference:
http://php.net/manual/en/function.strtoupper.php

My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.