Printing Unwanted Characters with PHP “preg_match”?

To print unwanted characters, use preg_match_all(). Let’s say the following is our string with some special characters −

$sentence= "M-y Name/i_s John+Doe";

We want the output to display only the special characters from the above string i.e.



The PHP code is as follows

 Live Demo

<!DOCTYPE html>
$sentence= "M-y Name/i_s John+Doe";
echo "The original value is=",$sentence,"<br>";
if(preg_match_all('/[^a-zA-Z ]/', $sentence, $output) ){
   echo "The unwanted characters are as follows= " . implode('', $output[0]);


This will produce the following output

The original value is=M-y Name/i_s John+Doe
The unwanted characters are as follows= -/_+