Question

注意：未定义的变量：dbname

未找到用户名

我不能从mysql db获取用户名和密码，也许你知道猫是什么问题？

............................................... .............................................

使page2.php

<?php
session_start();
?>
<html>
<head>
</head>
<body>
<?php
require ('sql_connect.php');
if(isset($_POST['submitlogin'])){
  $username = mysql_escape_string($_POST['usernameinput']);
  $password = mysql_escape_string($_POST['passwordinput']);
    if($username == $dbname){
      if($password == $dbpass){
        $_SESSION['currentuser'] = $username;
        $_SESSION['currentaccesslevel'] = 5;
        echo "welcome back, " . $username;
      }
      else {
        showform('wrong password');
      }
    }
    else {
      showform("username not found");
    }
  }
  else {
    showform("please enter your username and password");
  }
  function showform($message){
  include ('form.php');
  echo $message;
}
exit();
mysql_query("SELECT * FROM `user_data` WHERE `username`='$dbname' `password`='$dbpass'");
?>

............................................... ..............................................

sql_connect.php

<?php
mysql_connect("localhost", "root", "") or die("mysql connection is failure.");
mysql_select_db("users") or die("Database does not exists.");
?>

............................................... ................................................ 的 form.php的

<html>
<head>
</head>
<body>

<form method="post" action="page2.php" />
<input type="text" name="usernameinput" />
<input type="text" name="passwordinput" />
<input type='submit' value='submit' name='submitlogin' />
</form>

</body>
</html>

............................................... .........................................

Answer 1

您必须先定义$dbname才能使用它们。在上面的代码中，$dbname未定义，您正在比较它。这就是错误即将到来的原因。

if($username == $dbname){
if($password == $dbpass){

定义他们fisrt

$dbname = //some value;
$dbpass = //some value;

if($username == $dbname){
if($password == $dbpass){

注意：未定义的变量：dbname

1 个答案: