查询在php中检查测验

Question

查询是我选择正确答案的问题。 。 。 。 请回答我的问题

*

<?php
$sql = "SELECT * FROM questions_exam_tbl WHERE exam_id = '" . $_POST['subject'] . "'";
$result = mysql_query($sql) or die(mysql_error());
while($row = mysql_fetch_array($result)){
    if($row['test_num'] = $qnumber){
        echo '
        <h3>' . $row['test_num']. '. ' . $row['test_question'] . '</h1>
        <input type="radio" name="choiceA" value="' . $row['choice_A'] . '"> ' . $row['choice_A'] . '
        <input type="radio" name="choiceA" value="' . $row['choice_B'] . '"> ' . $row['choice_B'] . '
        <input type="radio" name="choiceA" value="' . $row['choice_C'] . '"> ' . $row['choice_C'] . '
        <input type="radio" name="choiceA" value="' . $row['choice_D'] . '"> ' . $row['choice_D'] . '
        ';  
    }
}
?>

*

Answer 1

if($row['test_num'] = $qnumber)

应该是

if($row['test_num'] == $qnumber)

单=用于值分配。为了进行比较，它是==或===。