サマリー：<?php     if(isset($_POST["submit"]) && $_POST["submit"] == "登陸")     {      &n

<?php 

    if(isset($_POST["submit"]) && $_POST["submit"] == "登陸") 

    { 

        $user = $_POST["username"]; 

        $psw = $_POST["password"]; 

        if($user == "" || $psw == "") 

        { 

            echo "<script>alert('請輸入用戶名或密碼！'); history.go(-1);</script>"; 

        } 

        else 

        { 

            mysql_connect("localhost","root","sixx"); 

            mysql_select_db("vt"); 

            mysql_query("set names 'gbk'"); 

            $sql = "select username,password from user where username = '$_POST[username]' and password = '$_POST[password]'"; 

            $result = mysql_query($sql); 

            $num = mysql_num_rows($result); 

            if($num) 

            { 

                $row = mysql_fetch_array($result);  //將數(shù)據(jù)以索引方式儲存在數(shù)組中 

                echo $row[0]; 

            } 

            else 

            { 

                echo "<script>alert('用戶名或密碼不正確！');history.go(-1);</script>"; 

            } 

        } 

    } 

    else 

    { 

        echo "<script>alert('提交未成功！'); history.go(-1);</script>"; 

    } 

?>

添削の先生：天蓬老師添削時間：2019-04-08 09:52:32
先生のまとめ：登錄處理, 如果后面不需要執(zhí)行,應(yīng)該加一條exit()這樣好些, 以防止在頁面中輸出一些無關(guān)的內(nèi)容