php - 注意：未定义的索引 php

Question

我收到错误通知：未定义索引：第 21 行 D:\pinnaclequizsoft\USBWebserver v8_en\root\test.php 中的 q_id 注意：未定义索引：D:\pinnaclequizsoft\USBWebserver v8_en\root\test.php 中的选项在线22

谁能告诉我我做错了什么？这是我的代码

<?php 
$link = mysql_connect('localhost', 'root', 'usbw');
if (!$link) {die('Could not connect: ' . mysql_error());}
$select = mysql_select_db("quiz",$link);

if (!$select)
{
    die('Could not Connect to Database');
}

$perpage = 1;

if(isset($_GET['id'])){
    $start = $_GET['id'];
}else{
    $start = 0;
}



$id= $_POST['q_id'];
$value = $_POST['option'];

$sql = "INSERT INTO ans "."(ques_id, ans_s) "."VALUES('$id','$value')";
mysql_select_db('quiz');
$retval = mysql_query( $sql, $link );
if(! $retval )
{
  die('Could not enter data: ' . mysql_error());
}
echo "Entered data successfully\n";


$TotalRec = mysql_num_rows(mysql_query("SELECT * FROM ques_bank"));

$select = "SELECT * FROM ques_bank LIMIT $start, $perpage";
$result = mysql_query($select) or die(mysql_error());
$rows = mysql_fetch_array($result);
 ?>
<form action="test.php?id=<?php echo ($start + 1); ?>" method="post">
<?php echo $rows['id'].". ". $rows['ques']; ?> <br>
<input type="radio" name="option" value="a"><?php echo $rows['optionA']; ?><br>
<input type="radio" name="option" value="b"><?php echo $rows['optionB']; ?><br>
<input type="radio" name="option" value="c"><?php echo $rows['optionC']; ?><br>
<input type="radio" name="option" value="d"><?php echo $rows['optionD']; ?><br>
<input type="radio" name="option" value="e"><?php echo $rows['optionE']; ?><br>
<input type="hidden" value="<?php echo $rows['id'] ?>" name="q_id">


<?php
if($start == 0){
    echo "Previous &laquo;";
}else{
    echo "<a href=\"./test.php?id=" . ($start - 1) . "\">Previous &laquo;</a>";
}

echo "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;";
if($start == $TotalRec-1){
    echo "Next &raquo;";
}else{
    echo "<a href=\"./test.php?id=" . ($start + 1) . "\">Next &raquo;</a>"; ?>
    <input type='Submit' value='SUBMIT & NEXT' name="next">
<?php    
}  
?>
</form>

Answer 1

您需要初始化 q_id

if(isset($_POST['q_id']))
   $id= $_POST['q_id'];

做print_r($sql)orprint_r($_POST)看看 q_id 是否通过