Question

我在Visual Basic中编写了一小段代码，用于在本地托管的login.php上发布用户名和密码，这种工作方式很有用，但由于某种原因，PHP脚本完全跳过if语句检查是否设置了参数username，并返回-1。

PHP代码：

$connection = mysqli_connect('127.0.0.1', 'root', 'root', 'default');
if(mysqli_connect_errno()) stop('2');

if(isset($_POST['username']) == true) {
    if(isset($_POST['password']) == true) {

        $username = mysqli_escape_string($connection, $_POST['username']);
        $password = mysqli_escape_string($connection, $_POST['password']);

        $query = mysqli_query($connection, "SELECT username,password,usersalt FROM Users WHERE username='$username';");

        if($result = $query) {
            while($row = mysqli_fetch_row($result)) {
                if($username == $row[0]) {
                    $password = sha1($password.$row[2]);

                        if($password == $row[1]) {
                            stop('5');
                        }

                    stop('4');
                } else { stop('3'); }
            }
        }
    } else { stop('1'); }
} else { stop('0'); }

stop('-1'); // Returns at this no matter what.

function stop($m) { global $connection;
    mysqli_close($connection);
    exit($m);
}

VB代码：

Public Function Login(Username As String, Password As String) As Int32
    Try
        If Username Is Nothing Then Return 0
        If Password Is Nothing Then Return 1

        Console.WriteLine("Establishing connection to login server")

        Dim Request As WebRequest = WebRequest.Create(Server & APIRequest.Login)
        Request.Method = "POST"
        Request.ContentType = "application/x-www-form-urlencoded"

        Dim Content As Byte() = Encoding.UTF8.GetBytes(String.Format("username={0}&password={1}", Username, Password))
        Request.ContentLength = Content.Length

        Console.WriteLine("Passing credentials to server")

        Dim DataStream As Stream = Request.GetRequestStream()
        DataStream.Write(Content, 0, Content.Length)
        DataStream.Close()

        Dim Response As WebResponse = Request.GetResponse()
        DataStream = Response.GetResponseStream()

        Console.WriteLine("Getting server response")

        Dim Reader As New StreamReader(DataStream)
        Dim ResponseString As String = Reader.ReadToEnd

        Reader.Close()
        DataStream.Close()
        Response.Close()

        If ResponseString IsNot Nothing Then
            Dim int As Int32 = -1
            Integer.TryParse(ResponseString, int)

            Console.WriteLine("Server response: {0}", int)

            Return int
        End If
    Catch Exception As Exception
    End Try

    Console.WriteLine("Unknown error occurred.")
    Return -1
End Function

VB输出：

Establishing connection to login server
Passing credentials to server
Getting server response
Server response: -1

更新

我已经解决了发生在线上的错误：
while($row = mysqli_fetch_row($result)) {

我用以下代码替换了这行代码：
$row = mysqli_fetch_row($result);

Answer 1

更改此

$connection = mysqli_connect('127.0.0.1', 'root', 'root', 'default');
if($connection->connect_errno()) stop('2');//add connection name

简要

添加此$connection->
更改此connect_errno()

Answer 2

我已经解决了发生在线上的错误：
while($row = mysqli_fetch_row($result)) {

我用以下代码替换了这行代码：
$row = mysqli_fetch_row($result);

PHP跳过if块

2 个答案: