Question

以下代码应该用于预定大学的讲座。当用户输入他们想要参加的讲座的详细信息时，代码会执行所有查询（2）并发布到数据库。

声明＆＃34; if ($totalrows<=5)＆＃34;没有工作（没有错误），这应该将预订的数量锁定为5以上的讲座，并且消息是回声。仍然是新手，并将感谢任何帮助。

<?php
session_start();
$usernm   = "root";
$passwd   = "";
$host     = "localhost";
$database = "swift";

mysql_connect($host, $usernm, $passwd);
mysql_select_db($database);

$existingusername = $_SESSION['myssession'];

$Unit_id   = $_POST['Unit_id'];
$User_name = $_POST['User_name'];
$Date      = $_POST['Date'];
`
`
$Lecture_id = $_POST['Lecture_id'];
$Room_name  = $_POST['Room_name'];


if ($Unit_id == "0001") {
    $values    = "SELECT * FROM lecturedetails WHERE Unit_id='0001'";
    $result    = mysql_query($values);
    $totalrows = mysql_num_rows($result);

    if ($totalrows <= 5) {
        $savevalues = "INSERT INTO delegate_booking VALUES('$Unit_id','$User_name','$Date','$Lecture_id','$Room_name')";
        $saveresult = mysql_query($savevalues);

    } else {
        echo "Bookings are full or late booking";
    }


    if ($Unit_id == "0002") {
        $values    = "SELECT * FROM lecturedetails WHERE Unit_id='0002'";
        $result    = mysql_query($values);
        $totalrows = mysql_num_rows($result);

        if ($totalrows <= 5) {
            $savevalues = "INSERT INTO delegate_booking VALUES('$Unit_id','$User_name','$Date','$Lecture_id','$Room_name')";
            $saveresult = mysql_query($savevalues);

        } else {
            echo "Bookings are full or late booking";
        }
    }
}
?>

<form action="LOGOUT.PHP">
    <input type="submit" value="LOG OUT"/>
</form>

<tr>
    <td><a href="Delegate.html">Back to Delegate member area</a></td>
</tr>

Answer 1

您获得的示例包含重复的代码，不必要的变量检查（但也错过了输入验证（！）），嵌套被破坏，客户端库已经过时了。

以下是如何解决这些问题的大部分而不是缺少输入值检查的示例，因为没有关于您在那里使用的字符串格式的规范。

<?php
session_start();
$existingusername = $_SESSION['myssession'];

$Unit_id   = $_POST['Unit_id'];
$User_name = $_POST['User_name'];
$Date      = $_POST['Date'];

$Lecture_id = $_POST['Lecture_id'];
$Room_name  = $_POST['Room_name'];

$pdo = new PDO(
    'mysql:host=localhost;dbname=swift;charset=utf8', "root", "",
    [PDO::ATTR_EMULATE_PREPARES => false, PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]
);

$count = function ($Unit_id) use ($pdo) {
    $stmt = $pdo->prepare('SELECT COUNT(*) FROM lecturedetails WHERE Unit_id = ?');
    $stmt->execute([$Unit_id]);
    return $stmt->fetchColumn();
};

$insert = function ($Unit_id, $User_name, $Date, $Lecture_id, $Room_name) use ($pdo) {
    $insert = $pdo->prepare("INSERT INTO delegate_booking VALUES(?, ?, ?, ?, ?)");
    $result = $insert->execute([$Unit_id, $User_name, $Date, $Lecture_id, $Room_name]);
};

if ($count($Unit_id) <= 5) {
    $insert($Unit_id, $User_name, $Date, $Lecture_id, $Room_name);
} else {
    echo "Bookings are full or late booking";
}

?>

<form action="LOGOUT.PHP">
    <input type="submit" value="LOG OUT"/>
</form>

<tr>
    <td><a href="Delegate.html">Back to Delegate member area</a></td>
</tr>

这对你有所帮助。如前所述，您检查错误表的行数的逻辑问题仍然没有修复。

Answer 2

我认为你的括号错了。 if($Unit_id=="0002")位于if($Unit_id=="0001")内，不应该是正确的。

$ existingusername = $ _ SESSION [＆＃39; myssession＆＃39;];

$ UNIT_ID = $ _ POST [＆＃39; UNIT_ID＆＃39;]; $ USER_NAME = $ _ POST [＆＃39; USER_NAME＆＃39;];   $ Date = $ _ POST [＆＃39; Date＆＃39;]; $ Lecture_id = $ _ POST [＆＃39; Lecture_id＆＃39;];   $ ROOM_NAME = $ _ POST [＆＃39; ROOM_NAME＆＃39;];
if($Unit_id=="0001")
  {                <-- start here
$ values =＆＃34; SELECT * FROM lecturedetails WHERE Unit_id =＆＃39; 0001＆＃39;＆＃34 ;; $结果= mysql_query（$值）; $ totalrows = mysql_num_rows（$结果）;
    if ($totalrows<=5)
    {
    $savevalues= "INSERT INTO delegate_booking VALUES('$Unit_id','$User_name','$Date','$Lecture_id','$Room_name')"; 
    $saveresult=mysql_query($savevalues);

    }
    else
    {
    echo "Bookings are full or late booking";
    }


if($Unit_id=="0002")
  { $values="SELECT * FROM lecturedetails WHERE Unit_id='0002'"; $result=mysql_query($values); $totalrows=mysql_num_rows($result);

    if ($totalrows<=5)
    {
    $savevalues= "INSERT INTO delegate_booking VALUES('$Unit_id','$User_name','$Date','$Lecture_id','$Room_name')"; 
    $saveresult=mysql_query($savevalues);

    }
    else
    {
    echo "Bookings are full or late booking";
    }
  }
  }                 <-- end here, why?
＆GT;

PHP / MySQL查询重复

2 个答案: