$str = "upper";

//php string to uppercase

echo strtoupper($str); // => UPPER

//string to all uppercase

$string = "String with Mixed use of Uppercase and Lowercase";

//php string to uppercase

$string = strtoupper($string);

// = "STRING WITH MIXED USE OF UPPERCASE AND LOWERCASE"

string strtoupper ( $string )

​

<?php

$str = "Mary Had A Little Lamb and She LOVED It So";

$str = strtoupper($str);

echo $str; // show: MARY HAD A LITTLE LAMB AND SHE LOVED IT SO

<?php

$str = "Mary Had A Little Lamb and She LOVED It So";

$str = strtoupper($str);

echo $str; // Prints MARY HAD A LITTLE LAMB AND SHE LOVED IT SO

?>