使用PHP中的较短代码验证多个输入

Question

The below code shows the process of validating 2 input fields. At the end i return in Json the Boolean result of each input.

Imagine i will do the following 20 more times, the code is large. How can an i perform the same procedure with shorter code?

$res =false;
$res2 = false;
    if(isset($_POST['Ans1'])) //if user checked ans1 radio
        {
          if($_POST['Ans1'] == "x divides y") #correct answer
          {
                $res = true;
          }
          else{#wrong answer
              $res = false;
          }
        }
        else{ #not checked
            $res = false;  
        }


        if(isset($_POST['Ans2'])) //if user checked ans2 radio
        {
          if($_POST['Ans2'] == "x greater than y") #correct answer
          {
                $res2 = true;
          }
          else{#wrong answer
              $res2 = false;
          }
        }
        else{ #not checked
            $res2 = false;
        }

        echo json_encode(['an1'=>$res,'an2'=>$res2]); 

Answer 1

You can use a function to check answer like this one:

function checkAnswer($key, $val) {
    $mapping = [
        'Ans1' => 'x divides y',
        'Ans2' => 'x greater than y'
    ];

    return $mapping[$key] == $val;
}

You will need a mapping of answers. You can then loop the POST array to check the answers; if POST only has answers.

$result = [];
foreach($_POST as $key => $val) {
    $res = checkAnswer($key, $val);
    $result[$key] = $res;
}
echo json_encode($result);