Form Validation

foreach( $_POST as $value ){

    if( stripos($value,'Content-Type:') !== FALSE ){

       echo "There was a problem with the information you have entered.";

        exit();

    }

}

This code appeared on a quiz and I couldn't find any reference to it in the video that it referred me to for the answer.

While I understand the concept of wanting to make sure the "content type" is contained within the value of each form post. I don't understand how I would apply this method to prevent a bot from hijacking my form.

Or better yet how checking to see if a string value is within the variable can even really check to see if the content type is right, if that was even what they were insinuating to begin with.

If anyone can shed some light on this I would be grateful.

Here is a link to the Video: Validating Form Data

Here is a link the Quiz: Form Validation