无法使单选按钮检查工作（PHP）

Question

I'm writing a small little webpage with 5 sickle cell anemia questions. I'm using the isset function to check the form elements and see if the user has selected a radio button for all 5 questions. But I cannot seem to make it work. What am I doing wrong?

<?php

    if (isset($_POST['q1','q2','q3','q4','q5'])) {
        echo 'Your score is <font size="24" color="red">' . $score . '</font> out of 100';
    }    else { 
        echo "Please answer all questions";
    }

?> 

Answer 1

You are not writing isset in correct way:-

    if (isset($_POST["q1"],$_POST["q2"],$_POST["q3"],$_POST["q4"],$_POST["q5"])) {
        echo 'Your score is <font size="24" color="red">' . $score . '</font> out of 100';
    }    else { 
        echo "Please answer all questions";
    }

?> 

If not understandable or you want to know exactly how's it working then read isset and array manual please.