我想在点击提交按钮后记住特定输入的值吗？目的是，如果用户在注册帐户时遇到电子邮件存在或密码不匹配等错误，我想保留姓名、年龄等值。这是我的代码，我该怎么办？有什么帮助或建议吗？感谢
<?php
session_start();
$errflag = false;
$errmsg = array();
if(isset($_SESSION['errmsg'])&&is_array($_SESSION['errmsg'])&&count($_SESSION['errmsg'])>0){
foreach($_SESSION['errmsg'] as $msg){
echo $msg;
}
unset($_SESSION['errmsg']);
}
?>
<form method="post">
<table>
<tr>
<td>Last Name:</td><td><input id="txtfield" type="text" name="lname" autofocus="autofocus" required="required"></td>
</tr>
<tr>
<td>First Name:</td><td><input id="txtfield" type="text" name="fname" required="required"></td>
</tr>
<tr>
<td>E-mail:</td><td><input id="txtfield" type="email" name="email" required="required"></td>
</tr>
<tr>
<td>Password:</td><td><input id="txtfield" type="password" name="pass" pattern=".{6,}" required="required"></td>
</tr>
<tr>
<td>Re-type:</td><td><input id="txtfield" type="password" name="rpass" pattern=".{6,}" required="required"></td>
</tr>
<tr>
<td></td><td><input id="btn" type="submit" name="register" value="Register"></td>
</tr>
</table>
</form>
<?php
include 'functions/functions.php';
if(isset($_POST['register'])){
$result=ValidateEmail($_POST['email']);
if($result){
$errmsg[] = '<p id="error"><img src="img/error.png" alt="error">This email address is already in use.</p>';
$errflag = true;
}
if($_POST['pass']!=$_POST['rpass']){
$errmsg[] = '<p id="error"><img src="img/error.png" alt="error">Passwords does not match.</p>';
$errflag = true;
}
if($errflag){
session_regenerate_id();
$_SESSION['errmsg'] = $errmsg;
session_write_close();
$errflag = false;
header('location: register.php');
exit();
}
else {
$user = array('lname'=>$_POST['lname'],'fname'=>$_POST['fname'],'email'=>$_POST['email'],'pass'=>$_POST['pass']);
RegisterUser($user);
session_regenerate_id();
$errmsg[] = '<p id="success"><img src="img/success.png" alt="success">Your account is now active. You may now login.</p>';
$_SESSION['errmsg'] = $errmsg;
session_write_close();
header('location: index.php');
exit();
}
}
?>
使用ajax/javascript检查密码是否不匹配或用户名是否已存在。这样，您就可以在不实际更改页面的情况下查询数据库。
所以你已经填好了，留在那里。以下是w3schools 的一个小示例
<form method="post">
<input id="txtfield" type="text" name="lname" autofocus="autofocus" required="required" Value=<?php $lname ?>/>
已经发布回同一页面。你现在可以做的是：
$lname = ""; //and all the other fields
$fname = "";
if ($_POST['lname'] == "")
{
$fname = $_POST['fname'];//and all the other fields
//put all the variables back into the form and display an error text
}
else
{
//Lets do the whole form processing and submit here
}
换句话说，使用空白变量设置输入字段的所有值。如果发生错误，请将所有这些变量设置为其原始值。
根据我的理解，如果提交错误或丢失，您希望提交的变量再次出现在表单中。
用这个替换HTML代码，它应该这样做：
<form method="post">
<table>
<tr>
<td>Last Name:</td><td><input id="txtfield" type="text" name="lname" value="<?=$_POST['lname'];?>" autofocus="autofocus" required="required"></td>
</tr>
<tr>
<td>First Name:</td><td><input id="txtfield" type="text" name="fname" value="<?=$_POST['fname'];?>" required="required"></td>
</tr>
<tr>
<td>E-mail:</td><td><input id="txtfield" type="email" name="email" value="<?=$_POST['email'];?>" required="required"></td>
</tr>
<tr>
<td>Password:</td><td><input id="txtfield" type="password" name="pass" pattern=".{6,}" required="required"></td>
</tr>
<tr>
<td>Re-type:</td><td><input id="txtfield" type="password" name="rpass" pattern=".{6,}" required="required"></td>
</tr>
<tr>
<td></td><td><input id="btn" type="submit" name="register" value="Register"></td>
</tr>
</table>
</form>