我知道您可能希望将其发布为重复的帖子，但是我完成了我的研究并尝试了一切，但仍无法使它正常工作，我正在用html，php和css做题字形式，我有两个问题，未定义的变量：数据库，并在null上调用成员函数prepare（）。 代码中突出显示的部分是我正在处理的内容以及问题的出处。我有两页代码（带有CSS的3页，但我不会包括在内），并且我正在使用php 5.6.35，如果还有其他问题，请随时提出，但是我最近开始编程，所以我可能不知道您在做什么。在谈论。谢谢 （我试图使用户两次没有相同的电子邮件，如果可能的话，请给我类似的id，以帮助我确保用户在我的一个代码表中已经包含“日期”输入的情况下达到13岁以上，再次感谢！）
index2.php：
<?php
if(!empty($_POST["register-user"])) {
/* Form Required Field Validation */
foreach($_POST as $key=>$value) {
if(empty($_POST[$key])) {
$error_message = "All Fields are required";
break;
}
}
/* Password Matching Validation */
if($_POST['password'] != $_POST['confirm_password']){
$error_message = 'Passwords should be same<br>';
}
/* Email Validation */
if(!isset($error_message)) {
if (!filter_var($_POST["userEmail"], FILTER_VALIDATE_EMAIL)) {
$error_message = "Invalid Email Address";
}
}
/* Validation to check if gender is selected */
if(!isset($error_message)) {
if(!isset($_POST["gender"])) {
$error_message = " All Fields are required";
}
}
/* Validation to check if Terms and Conditions are accepted */
if(!isset($error_message)) {
if(!isset($_POST["terms"])) {
$error_message = "Accept Terms and Conditions to Register";
}
}
if(!isset($error_message)) {
require_once("dbcontroller.php");
$db_handle = new DBController();
$query = "INSERT INTO members (username, firstname, lastname, password, email, gender, dob) VALUES
('" . $_POST["userName"] . "', '" . $_POST["firstName"] . "', '" . $_POST["lastName"] . "', '" . md5($_POST["password"]) . "', '" . $_POST["userEmail"] . "', '" . $_POST["gender"] . "' , '" . $_POST["dob"] . "' )";
$result = $db_handle->insertQuery($query);
if(!empty($result)) {
$error_message = "";
$success_message = "You have registered successfully!";
unset($_POST);
} else {
$error_message = "Problem in registration. Try Again!";
}
}
}
?>
<html>
<?php
include 'C:\wamp64\www\Etego\stylesignup.css';
?>
<head>
<title>PHP User Registration Form</title>
</head>
<body>
<form name="frmRegistration" method="post" action="">
<table border="0" width="500" align="center" class="demo-table">
<?php if(!empty($success_message)) { ?>
<div class="success-message"><?php if(isset($success_message)) echo $success_message; ?></div>
<?php } ?>
<?php if(!empty($error_message)) { ?>
<div class="error-message"><?php if(isset($error_message)) echo $error_message; ?></div>
<?php } ?>
<tr>
<td>User Name</td>
<td><input type="text" class="demoInputBox" name="userName" value="<?php if(isset($_POST['userName'])) echo $_POST['userName']; ?>"></td>
</tr>
<tr>
<td>First Name</td>
<td><input type="text" class="demoInputBox" name="firstName" value="<?php if(isset($_POST['firstName'])) echo $_POST['firstName']; ?>"></td>
</tr>
<tr>
<td>Last Name</td>
<td><input type="text" class="demoInputBox" name="lastName" value="<?php if(isset($_POST['lastName'])) echo $_POST['lastName']; ?>"></td>
</tr>
<tr>
<td>Password</td>
<td><input type="password" class="demoInputBox" name="password" value=""></td>
</tr>
<tr>
<td>Confirm Password</td>
<td><input type="password" class="demoInputBox" name="confirm_password" value=""></td>
</tr>
<tr>
<td>Email</td>
<td><input type="text" class="demoInputBox" name="userEmail" value="<?php if(isset($_POST['userEmail'])) echo $_POST['userEmail']; ?>"></td>
</tr>
<tr>
<td>Date Of birth</td>
<td><input type="date" value="<?php print(date("YYYY-MM-DD"))?>" class="demoInputBox" name="dob" value="<?php if(isset($_POST['dob'])) echo $_POST['dob']; ?>"></td>
</tr>
<tr>
<td>Gender</td>
<td><input type="radio" name="gender" value="Male" <?php if(isset($_POST['gender']) && $_POST['gender']=="Male") { ?>checked<?php } ?>> Male
<input type="radio" name="gender" value="Female" <?php if(isset($_POST['gender']) && $_POST['gender']=="Female") { ?>checked<?php } ?>> Female
<input type="radio" name="gender" value="not specified" <?php if(isset($_POST['gender']) && $_POST['gender']=="not specified") { ?>checked<?php } ?>> not specified
</td>
</tr>
<tr>
<td colspan=2>
<input type="checkbox" name="terms"> I accept <a href="terms.html">Terms and Conditions</a> <input type="submit" name="register-user" value="Register" class="btnRegister"></td>
</tr>
</table>
</form>
</body></html>
dbcontroller.php：
<?php
class DBController {
public $host = "localhost";
public $user = "root";
public $password = "";
public $database = "members";
public $conn;
function __construct() {
$this->conn = $this->connectDB();
}
function connectDB() {
$conn = mysqli_connect($this->host,$this->user,$this->password,$this->database);
return $conn;
}
function runQuery($query) {
$result = mysqli_query($this->conn,$query);
while($row=mysqli_fetch_assoc($result)) {
$resultset[] = $row;
}
if(!empty($resultset))
return $resultset;
}
function numRows($query) {
$result = mysqli_query($this->conn,$query);
$rowcount = mysqli_num_rows($result);
return $rowcount;
}
function updateQuery($query) {
$result = mysqli_query($this->conn,$query);
if (!$result) {
die('Invalid query1: ' . mysqli_error($this->conn));
} else {
return $result;
}
}
function insertQuery($query) {
$result = mysqli_query($this->conn,$query);
if (!$result) {
die('Invalid query2: ' . mysqli_error($this->conn));
} else {
return $result;
}
}
function deleteQuery($query) {
$result = mysqli_query($this->conn,$query);
if (!$result) {
die('Invalid query3: ' . mysqli_error($this->conn));
} else {
return $result;
}
}
}
**[/* Email already exists */
/* line 63 */ $reqemail = $database->prepare("SELECT * FROM members WHERE email = ?");
$reqemail->execute(array($email));
$emailexist = $reqemail->rowCount();
if($emailexist == 0)
{
}
else
{
$error_message = "Email already exists";
}
//end of email existance][1]**
?>