Question

我正在参加培训课程申请，这对我来说是第一次，所以我遇到了一些障碍。我有一个表单，即培训评估，在提交时，会向php页面发送一系列id和所选答案进行处理。我的想法是运行一个mysql查询选择一个正确答案的计数，然后另一个选择一个不同的问题的计数，然后将两个除以计算得分。这一部分很简单，但我的思绪正在融化，试图找出选择正确答案数的查询。

以下是我的表单的代码......

<form name="assessment" method="post" action="scripts/scoreAssessment.php">
  <ul class="assessment">
    <li class='question'>This is a question? 
      <ul style='list-style:none;'>
        <li><input name='trainingCourseAnswer[]' type='radio' value='A1'/>This is a multiple choice answer.</li>
        <li><input name='trainingCourseAnswer[]' type='radio' value='B1'/>This is a multiple choice answer.</li>
        <li><input name='trainingCourseAnswer[]' type='radio' value='C1'/>This is a multiple choice answer.</li>
        <li><input name='trainingCourseAnswer[]' type='radio' value='D1'/>This is a multiple choice answer.</li>
      </ul>
    </li>
    <li class='question'>This is a question? 
      <ul style='list-style:none;'>
        <li><input name='trainingCourseAnswer[]' type='radio' value='A2'/>This is a multiple choice answer.</li>
        <li><input name='trainingCourseAnswer[]' type='radio' value='B2'/>This is a multiple choice answer.</li>
        <li><input name='trainingCourseAnswer[]' type='radio' value='C2'/>This is a multiple choice answer.</li>
        <li><input name='trainingCourseAnswer[]' type='radio' value='D2'/>This is a multiple choice answer.</li>
      </ul>
    </li>
    <!--continue pattern for total number of questions-->
  </ul>
  <input name='submitAssessment' type='submit' value='Finish Test'/>
</form>

在scoreAssessment.php中，我可以使用PHP substr函数拆分所选无线电输入答案的值，以获得两个变量$ selectedAnswer和$ answerID。我需要运行以选择所有正确答案的查询如下...

$selectedAnswer=substr($_POST['trainingCourseAnswer'], 0, 1);
$answerID=substr($_POST['trainingCourseAnswer'], 1);
$query="SELECT COUNT(correctAnswer) WHERE answerID='$answerID' AND correctAnswer='$selectedAnswer'"

我遇到的问题是$ answerID和$ selectedAnswer都是具有多个值的数组......

有人可以提供一些指导吗？我将不胜感激！

Answer 1

首先，您会注意到，使用提供的HTML，用户只能从8个选项中选择一个答案。这不是您想要的：您希望每个问题允许一个选择。这可以通过给无线电控件提供不同的名称来解决：每个问题一个唯一的名称。而且你也不需要数组符号，因为每个问题你将不会有多个答案：

<form name="assessment" method="post" action="scripts/scoreAssessment.php">
  <ul class="assessment">
    <li class='question'>This is a question? 
      <ul style='list-style:none;'>
        <li><input name='q1' type='radio' value='A'/>This is a multiple choice answer.</li>
        <li><input name='q1' type='radio' value='B'/>This is a multiple choice answer.</li>
        <li><input name='q1' type='radio' value='C'/>This is a multiple choice answer.</li>
        <li><input name='q1' type='radio' value='D'/>This is a multiple choice answer.</li>
      </ul>
    </li>
    <li class='question'>This is a question? 
      <ul style='list-style:none;'>
        <li><input name='q2' type='radio' value='A'/>This is a multiple choice answer.</li>
        <li><input name='q2' type='radio' value='B'/>This is a multiple choice answer.</li>
        <li><input name='q2' type='radio' value='C'/>This is a multiple choice answer.</li>
        <li><input name='q2' type='radio' value='D'/>This is a multiple choice answer.</li>
      </ul>
    </li>
    <!--continue pattern for total number of questions-->
  </ul>
  <input name='submitAssessment' type='submit' value='Finish Test'/>
</form>

因此，您不必将问题编号添加到单选按钮的 ABCD 值（您可以，但这不是必需的）。此外，我选择了较短的名称（q1，q2），因为较长的名称也会使URL长。

然后在PHP中，我建议从数组中的数据库表中读取所有正确答案，并将这些答案逐一与用户的答案进行比较，并保持计数。我在这里假设 mysqli _ 函数，但应该很容易将其转换为您喜欢的方法（如PDO）：

// Connection to database...
$con = mysqli_connect("my_host", "my_user", "my_password", "my_db");

// Check connection
if (mysqli_connect_errno()) {
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

// Read all correct answers from the database:
$query = "SELECT answerID, correctAnswer FROM answerTable";
$result = mysqli_query($con, $sql);

// Fetch all records into an associative array
$correctAnswers = mysqli_fetch_all($result, MYSQLI_ASSOC);

// Count correct answers provided by user (via POST)
$correctCount = 0;
foreach ($correctAnswers as $correctAnswer) {
    $answerID = $correctAnswer['answerID'];
    if (isset($_POST["q$answerID"])
            && $_POST["q$answerID"] == $correctAnswer['correctAnswer']) {
        $correctCount++;
    }
}
// Score is fraction between 0 and 1. Multiply by 100 for a percentage
$score = $correctCount / count($correctAnswers);

请注意，这样可以避免因SQL injection而导致的漏洞，因为上面的SQL语句未通过 POST 提交的值定义。

如何在mysql查询中使用已发布的输入数组？

1 个答案: