Get variables and handling null professionally

Question

I am using PHP's get method. What is the professional way to handle a null value in a get method. I don't want to see the sql errors on my website.

Answer 1

This will check if the variable is set and the variable doesn't equal an empty string - if its a number you are testing and it has to be more than 0 then swap out the "" for 0:

if (isset($_GET["myvar"]) && $_GET["myvar"] != "")
{
    //do your thing
}
else
{
    //if you do not wish to exit script comment this line out
    exit("There has been an error.");

    //use this instead
    $error = "There has been an error."
}

//and echo your error out later on your page if you require it
echo $error;