PHP strtoupper()

The strtoupper() function in PHP is just used to convert any string with letters into the uppercase letter format( Capital Letters Format ). This strtoupper() function takes just one string parameter mostly to convert all the lowercase English alphabet letters to uppercase English alphabet letters. The remaining characters, like numeric values and special characters, will remain the same even though the strtoupper() function is used to capitalize the alphabet. It is different from ucwords() function. It capitalizes all the alphabets/characters into capital letters.

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Syntax:

string strtoupper ( $string_variable );

Parameter:

There is only one parameter that is needed mainly. It is $string_variable only. Other than that, strtoupper() is a function that converts all lowercase letters present in the $string_variable into uppercase letters/capital letters.

How does PHP strtoupper() Work?

PHP strtoupper() function works in PHP 4, PHP 5, and PHP 7 versions. This function is compatible with only the PHP mentioned above versions. It works by converting the string, which mixes characters into capital letters, but it is done only with the alphabet.

The below-listed examples illustrate some of the little properties of strtoupper() function and some ways of programming listed to know how to use it.

Example #1

Code:

<?php // original string which is assigned to the str1 variable
$str1 = "educba is a leading global provider of skill based education";
// The string which will be converted to the upper case
$capstr1 = strtoupper($str1);
echo $capstr1;
?>

Output:

Example #2

It is an example of PHP syntax, which makes the string variable’s characters into capital letters.

Code:

<?php // original string which is assigned to the str1 variable
$str1 = "how Billgates & Pavan took the Top position in 2024 123$#%123";
echo "Original string : \n".$str1."|||";
// Now the string which is assigned to the str1 variable will be converted to upper case/capital letters
$str2 = strtoupper($str1);
echo "\n Output/ Modified String : "  ;
echo $str2;
//The above echo prints : HOW BILLGATES & PAVAN TOOK THE TOP POSITION IN 2014 123$#%123
?>

Output:

Example #3

It is the correct setting to set the local function. It will do the trick with an example of German umlauts because it is not always true. Here mb_strtoupper() function instead of strtoupper() function to capitalize even some special characters.

Setlocale() function is essential and can silently fail if it can’t be found in the specific/specified/particular locale on your PC/system. So one should always try to check its main return value. There will be various combinations of spellings to use locale like “de_AT”, “de” etc..,

If one doesn’t find a specific/appropriate locale setting configuration, recheck your system’s configuration. Check locale settings system-wide; PHP now gets them from the PC/Laptop/any other OS. In Windows, you set the locale using the control panel. However, in the Linux operating system, the method for setting the locale depends on the distribution you are using.

In Linux, you can try sudo after space dpkg-reconfigure locales on the Debian-based particular OS distros or configure them using the manual methods. On Ubuntu OS, you must copy the entries in the following URL location /usr / share /i18n /SUPPORTED, then prolong it to the / var/ lib /locales/ supported. d/local. After this, do the dpkg-reconfigure/reconfiguration. After completing this, restart the webserver and web browser sometimes.

Code:

<?php setlocale(LC_CTYPE, 'de_DE.UTF8');
$str2 = strtoupper('Umlaute1 äöü in uppercase  ||| '); ;
echo  $str2;// outputs "UMLAUTE1 äöü IN UPPERCASE" LETTERS
$str3 = mb_strtoupper('Umlaute1 äöü in uppercase', 'UTF-8');
echo $str3; // outputs "UMLAUTE1 ÄÖÜ IN UPPERCASE" LETTERS
?>

Output:

Example #4

Code:

<?php // PHP program in order to illustrate how to modify some data and capitalize it
// Progam to search and replace some specific data/matter and then to capitalize the modified data
// preg_replace () function used
$string1 = 'November 01, 2018';
$pattern1 = '/(\w+) (\d+), (\d+)/i';
$replacement1 = '${1} 02, $3';
// prints output of function below using the echo builtin function
echo " 1.Modified String :: ";
echo preg_replace($pattern1, $replacement1, $string1);
echo " ||| "; // Outputs/Prints "|||" in browser
echo "\n"; // Outputs/ Prints the Line Break to execute/display the next program later
$string2 = preg_replace($pattern1, $replacement1, $string1);
$string3 = strtoupper($string2);
echo " 2.Capitalized Modified String :: ";
echo $string3;
//Outputs the modified capitalized string
?>

Output:

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