php - 登录脚本显示空白页

Question

这段代码似乎不起作用。当我单击登录按钮时，它仅显示空白页面。可能是什么问题。

<?php
$username = mysql_real_escape_string($_POST['username']);
$password = mysql_real_escape_string($_POST['password']);

$con = mysql_connect("localhost","root","root");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

mysql_select_db("register", $con);

$query =("SELECT * FROM users WHERE username = '". $username ."' AND password = '". $password ."'     LIMIT 1");

$count = mysql_num_rows($query);
if ($count == 0) {
  echo 'Error: username or password wrong ';
} else {
  echo "Registration Successful, redirecting";

header("refresh:3; url=login.html");
mysql_close($con)
?>

Answer 1

使用 IDE 而不仅仅是编辑器!使用我的 IDE，它立即向我显示一个错误，并且随后很容易修复:

<?php
$username = mysql_real_escape_string($_POST['username']);
$password = mysql_real_escape_string($_POST['password']);

$con = mysql_connect("localhost","root","root");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

mysql_select_db("register", $con);

$query =("SELECT * FROM users WHERE username = '". $username ."' AND password = '". $password ."'     LIMIT 1");

$count = mysql_num_rows($query);
if ($count == 0) {
  echo 'Error: username or password wrong ';
} else {
  echo "Registration Successful, redirecting";

}

header("refresh:3; url=login.html");
mysql_close($con);
?>

您忘记了 else 部分的右大括号和倒数第二行中的分号!