我正试图在表单中创建一个php日志。我只想做一些调整，但当我修改它时，它就停止工作了。。。
如果您无法从代码中看到，我将尝试创建一个（模拟）登录表单，要求提供用户名和密码。
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我希望任何空白的文本框都在文本框的右侧显示一条红色消息。（我有红色错误信息，但我不能把它放在盒子的左边）
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我想要一个粘性表格，如果填写了任何一个字段，它都会保持（再次，我想我已经设置好了，但不认为它一直有效）
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我希望输入用户名user和密码abc123的人看到欢迎信息。如果你不使用用户名/密码组合，我想要一条消息，说他们没有被授权。（这是我真的不知道该怎么做）
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我想把这一切都放在一个redux中（也认为我有工作，但不是100%确定）
任何帮助都将不胜感激！！
这是我的代码：
<?php
define('TITLE', 'LOG IN');
// CSS
print '<style type="text/css" media="screen">
.error { color: red; }
</style>';
// Checking
if ( isset($_POST['submitted']) ) {
$problem = FALSE;
// Each value
if (empty($_POST['email'])) {
$problem = TRUE;
print '<p class="error">Please enter the username!</p>';
}
if (empty($_POST['password1'])) {
$problem = TRUE;
print '<p class="error">Please enter the password!</p>';
}
if (!$problem) { //No problem
// Printing the log in message
print '<p>Thank you for logging in!</p>';
$_POST = array();
} else {
print '<p class="error">No entry!</p>';
}
}
?>
<form action="login.php" method="post">
<p>"Username": <input type="text" name="username" size="20" value="<?php if (isset($_POST['username'])) { print htmlspecialchars($_POST['username']); } ?>" /></p>
<p>Password: <input type="password" name="password1" size="20" /></p>
<p><input type="submit" name="submit" value="Log in" /></p>
<input type="hidden" name="submitted" value="true" />
</form>
好的，这里有一个简单的登录，不适合在现实世界中使用。请阅读代码中的注释，看看我对每一条都有什么看法。由于多种原因，登录非常棘手，因此本示例并不旨在演示真实世界中可工作的代码库，而是一个非常简单的用户名/密码检查。
与更复杂的使用相关的安全问题可能超出了这个答案的范围，但下面的代码是我解释您在上面发布的内容的方式，而没有详细说明（可能会让人很难理解发生的最简单的步骤）。
如果你有任何问题，请告诉我。要查看正在运行的表单，请检查：
http://jfcoder.com/test/simplelogin.php
此外，为了简单起见，我使用了PHP的HEREDOC语法，而不是带引号的字符串。要阅读更多关于这个有时很方便的表格，请参阅
http://www.php.net/manual/en/language.types.string.php#language.types.string.syntax.heredoc.
<html>
<head>
<style type="text/css">
.error {
color: red;
}
</style>
</head>
<body>
<?php
// Note, in most cases you will set a SESSION variable
// of $_SESSION['loggedin'], which would require you to
// use session_start() before you access any session
// variables.
// Note, this defaults to false.
$loggedin = false;
// If I get an error, I will put it in this variable.
$error = '';
// If the username is provided, run the code. Otherwise,
// act as if the login form was not submitted. This makes
// a hidden `submitted` value superfluous, and guarantees
// your users at least provide a username.
if ($_POST['username']) {
// NOTE!!! In mose cases, you're querying a database
// for a username/password match. In PHP, this often
// means a MySQL query. DO NOT USE THE BELOW IF YOU
// ARE DOING SO!!! This will allow what's called a
// SQL injection. You MUST wash your data with something
// like mysql_real_escape_string() for the $_POST
// values (NEVER trust submitted data, always validate
// and escape as necessary), or use the PHP PDO library.
// In this example, though, I use a switch to check the
// values for exact matches, which means I do not need
// to escape (and mysql_real_escape_string() requires
// a database connection to use).
$username = $_POST['username'];
$password = $_POST['password'];
// Here, I check if the username and password match.
// This is, of course, hardcoded, but to match your
// attempt, I chose to keep the form, although you
// rarely see this in use in the real world.
switch ($username) {
// My one case. For each additional user, you
// would need to add a new entry with password
// check. And I set my error text according to
// the result of the code.
case 'user':
if ($password === 'abc123') {
$loggedin = true;
} else {
$error = 'Username/Password did not match.';
}
break;
default:
// Note, I don't give a descriptive error
// here. If someone reports this error, I
// know what may have gone wrong, but the
// user is not told the username does not
// exist.
$error = 'Unknown error. Try again.';
}
}
// I will only show the welcome message if the user has
// successfully logged in.
if ($loggedin === true) {
echo <<<HTML
<h1>Welcome!</h1>
<p>Thank you for logging in $username</p>
HTML;
} else {
// If an error text is set, display that error.
if ($error != '') {
$error = "<h4>Login error</h4><p class='error'>$error</p>";
}
// Here's my form, only shown if the user has not
// successfully logged in (note, this is only a one-
// time check when the POST data is submitted; I
// would need to use sessions to "remember" the requestor
// had logged in across page accesses.
echo <<<FORM
<h1>Login Form</h1>
<form action="simplelogin.php" method="POST">
$error
<p><label>Username: <input type="text" name="username"/></label></p>
<p><label>Password: <input type="password" name="password"/></label></p>
<p><input type="submit" value="Login"/> <input type="reset"/></p>
</form>
FORM;
}
?>
</body>
</html>
这是我的完整代码。我几乎重写了整件事，所以如果编码风格差异太大，我会道歉：
<?php
// Output our CSS code
echo '<style type="text/css" media="screen">
.error
{
color: red;
}
</style>';
// Define our variable
$problem = false;
// Check if the form has been submitted
if (isset($_POST['submitted']))
{
// If either user or password are empty, we have a problem
if (empty($_POST['username']) || empty($_POST['password']))
{
$problem = TRUE;
}
// If there is no problem, username is user, and password is abc123, we're good
if (!$problem && $_POST['username']=='user' && $_POST['password']=='abc123') {
// Print our login message
echo 'Thank you for logging in!<br />';
}
// Ok, there's either a problem or the username or password is wrong, so no entry for them
else
{
echo '<p class="error">No entry!</p>';
}
}
?>
<form action="login.php" method="post">
Username: <input type="text" name="username" size="20" value="<?php
if (isset($_POST['submitted']) && !empty($_POST['username']))
{
echo $_POST['username'];
} ?>" />
<?php
if (isset($_POST['submitted']) && empty($_POST['username']))
{
echo '<span class="error">Please enter a username!</span>';
}
?>
<br />Password: <input type="password" name="password" size="20" value="<?php
if (isset($_POST['submitted']) && !empty($_POST['password']))
{
echo $_POST['password'];
} ?>" />
<?php
if (isset($_POST['submitted']) && empty($_POST['password']))
{
echo '<span class="error">Please enter the password!</span>';
}
?>
<br /><input type="submit" value="Log in" />
<br /><input type="hidden" name="submitted" value="true" />
</form>