我有以下代码：
<html>
<head>
</head>
<body>
<?php
if (!isset($_COOKIE["loggedin"])){
?>
<form action="index.php" method="POST" name="name_form">
Username <input type="text" name="username">
<br/>
Password <input type="text" name="password">
<br/>
Remember Me <input type ="checkbox" name="remember_me" value="1">
<br/>
<input type="submit" name="submit" value="Log in">
</form>
<?php
if(preg_match("/<|>/", $_POST["username"])){
echo "do not log in";
}
else if(preg_match("/<|>/", $_POST["password"])){
echo "do not log in";
}
else {
//Open/create passwords.txt
$passwordsFile = fopen("passwords.txt", "a");
//write users username and password to passwords.txt
$text_written = fwrite($passwordsFile, $_POST["username"] . "," . $_POST["password"] . "'r'n");
fclose($passwordsFile);
setcookie("loggedin", $_POST["username"]);
setcookie("loggedintime", time());
echo "<h1>Welcome " . $_COOKIE["loggedin"] . "</h1>";
echo "You have been logged in for " . $_COOKIE["loggedintime"] . " seconds.";
echo "<nav>
<ul>
<li>Browse books in store</li>
<li>Analytics</li>
<li>Logout</li>
</ul>
</nav>";
}
}
?>
</body>
但它显示"欢迎____，您已登录..."部分在用户正确填写表单之前，如果我想仅在用户正确填写表单后显示它，我想知道该怎么办。
谢谢！
好吧，从逻辑上逐步完成你的代码。 如果用户未登录，则为真：
if (!isset($_COOKIE["loggedin"])){
如果没有发布表单值，则为假：
if(preg_match("/<|>/", $_POST["username"])){
这是错误的：
else if(preg_match("/<|>/", $_POST["password"])){
因此，执行else块。 完全按照设计。
我怀疑您想检查是否收到任何表单帖子。 在这种情况下，您可以将该代码包装为：
if (isset($_POST["submit"])){
这将在评估其余代码之前检查是否按下了submit按钮。
您似乎正在验证表单并显示欢迎消息而没有提交它。请检查下面的代码。它可能会对你有所帮助。仅在提交表单后验证表单。
<?php
if (!isset($_COOKIE["loggedin"])) {
?>
<form action="index.php" method="POST" name="name_form">
Username <input type="text" name="username">
<br/>
Password <input type="text" name="password">
<br/>
Remember Me <input type ="checkbox" name="remember_me" value="1">
<br/>
<input type="submit" name="submit" value="Log in">
</form>
<?php
if($_POST) {
if(preg_match("/<|>/", $_POST["username"])){
echo "do not log in";
}
else if(preg_match("/<|>/", $_POST["password"])){
echo "do not log in";
}
else {
//Open/create passwords.txt
$passwordsFile = fopen("passwords.txt", "a");
//write users username and password to passwords.txt
$text_written = fwrite($passwordsFile, $_POST["username"] . "," . $_POST["password"] . "'r'n");
fclose($passwordsFile);
setcookie("loggedin", $_POST["username"]);
setcookie("loggedintime", time());
echo "<h1>Welcome " . $_COOKIE["loggedin"] . "</h1>";
echo "You have been logged in for " . $_COOKIE["loggedintime"] . " seconds.";
echo "<nav>
<ul>
<li>Browse books in store</li>
<li>Analytics</li>
<li>Logout</li>
</ul>
</nav>";
}
}
}
?>