检查提交值是否在数组中？(Check wheter submitting value is in array?)

 我最近读过一篇文章说，你永远不应该信任发送数据中的用户。 
 
 所以我们假设我有以下表单输入： 
 
<label for="input1">Answer 1</label>
<input type="radio" name="question1" value="answer1" id="input1" />
<label for="input2">Answer 2</label>
<input type="radio" name="question1" value="answer2" id="input2" />
<label for="input3">Answer 3</label>
<input type="radio" name="question1" value="answer3" id="input3" />
 
 是否可以检查发布的答案是否在回答里面： 
 
$question1_answers = array("answer1", "answer2", "answer3");
$answer1 = $_POST['question1'];
if ( in_array($answer1, $question1_answers) ) {
    echo "OK!";
} else {
    echo "Please select proper answer!";
}
 
 或者，也许上面的代码是不必要的，我应该简单地阅读$_POST['question1'] ，这将足够？ 

I have recently read an article that said, that you should never trust user in the sending data.
 
So let's say that I have following form inputs:
 
<label for="input1">Answer 1</label>
<input type="radio" name="question1" value="answer1" id="input1" />
<label for="input2">Answer 2</label>
<input type="radio" name="question1" value="answer2" id="input2" />
<label for="input3">Answer 3</label>
<input type="radio" name="question1" value="answer3" id="input3" />
 
Is it okay to check whether posted answer is inside aray with answers:
 
$question1_answers = array("answer1", "answer2", "answer3");
$answer1 = $_POST['question1'];
if ( in_array($answer1, $question1_answers) ) {
    echo "OK!";
} else {
    echo "Please select proper answer!";
}
 
Or maybe above code is unnecessary and I should simply read $_POST['question1'] and it will be enough?

原文：https://stackoverflow.com/questions/12814021