为什么我在这里收到错误？

Question

只是尝试一些教程！无法弄清楚为什么我在表单操作行上出现错误

<?php
    if (isset($_POST['Username'])&&isset($_POST['password'])) {
        $username = $_POST['Username'];
        $password = $_POST['password'];
        if (!empty($Username)&&!empty($password)) {
        echo 'OK';  
        } else {
            echo 'You must supply an email and a password.';
        }
    ?>

    <form action="<?php echo $current_file; ?>" method="POST">
     Email: <input type="text" name="username"> Password: <input type="password" name="password">
     <input type ="submit" value = "Log In"  />

     </form>

Answer 1

$username = $_POST['Username'];
        $password = $_POST['password'];
        if (!empty($Username)&&!empty($password)) {

你有两个变量$ username和$ Username - 应该是一样的吗？

Answer 2

您需要关闭初始if条件块

Answer 3

可能是因为没有定义 $ current_file 吗？或者您是否在代码之前定义它？