strtoupper() to change lower to uppercase characters
$val=strtoupper($input_sting);
We can use strtoupper() function in PHP to change all the alphabetic characters to uppercase. This simple function takes one string as input and changes the characters present inside to uppercase.
Here is an example code.
$my_str="Hello welcome to plus2net.com";
$my_str=strtoupper($my_str);
echo $my_str;