Php 检查是否正在使用用户名
我想知道是否以及如何检查是否正在使用用户名 我听说你可以用jQuery来实现这一点，但我只是想要一些简单的东西，因为我是初学者 我已经试过了，但我无法把它做好。我只是将其连接到mysql数据库，但由于当一个用户名与另一个帐户的密码相同时尝试登录，因此出现了一个问题，因此我需要使用此功能来阻止人们添加多个用户名 下面是我的注册表单和php的简单代码Php 检查是否正在使用用户名,php,mysql,login,Php,Mysql,Login,我想知道是否以及如何检查是否正在使用用户名 我听说你可以用jQuery来实现这一点，但我只是想要一些简单的东西，因为我是初学者 我已经试过了，但我无法把它做好。我只是将其连接到mysql数据库，但由于当一个用户名与另一个帐户的密码相同时尝试登录，因此出现了一个问题，因此我需要使用此功能来阻止人们添加多个用户名 下面是我的注册表单和php的简单代码 姓名： 用户名： 电邮： 密码： 对于初学者来说，您不想仅仅依靠unique field之类的东西来实现这一点，当然，您希望在数据库中的用
姓名：
用户名：
电邮：
密码：
对于初学者来说，您不想仅仅依靠unique field之类的东西来实现这一点，当然，您希望在数据库中的用户名列中添加该属性，但在上面，您希望在其上方有某种正面保护，而不是依赖于数据库在插入时抛出错误，您还需要将mysqli用于所有这些，而不是旧版本mysql。它很容易被利用，不再是常见的做法，以下是您的每个文件的外观：
connect.php
register.php
用户名：
密码：
姓名：
电邮地址：
下面是另一个例子：），成功
<?php
//Set empty variables.
$usernameError = $emailError = $passwordError = $nameError = $okmsg = "";
$username = $password = $email = $name = "";
if (isset($_POST['submit'])) {
//Check if empty labels form
if (empty($_POST['name'])) {
$userError = "The 'name' is required.";
echo '<script>window.location="#registrer"</script>';
} else { $name = $_POST['name']; }
if (empty($_POST['email'])) {
$emailError = "El 'Email' es requerido.";
echo '<script>window.location="#registrer"</script>';
} else {
$email = $_POST['email'];
//Check only contain letters and whitespace.
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
$emailError = "El 'Email' is not valid. ";
echo '<script>window.location="#registrer"</script>';
}
}
if (empty($_POST['password'])) {
$passwordError = "The 'password' is requiered.";
echo '<script>window.location="#registrer"</script>';
} else {
$password = $_POST['password'];
}
}
//Check if correctly filled
if ($name && $username && $email && $password) {
require('connect.php');
//Query SQL
$sql = "SELECT * FROM user WHERE username='$username'"; //String SQL
$query = mysqli_query($ConDB, $sql);//Query
//Securite
$username = mysqli_real_escape_string($ConDB, $username);
$password = mysqli_real_escape_string($ConDB, $username);
$passw = sha1($password);//For securite.
$name = mysqli_real_escape_string($ConDB, $username);
$email = mysqli_real_escape_string($ConDB, $username);
if ($existe = mysqli_fetch_object($query)) {
$usernameError = "The 'Username' is already exists.";
echo '<script>window.location="#registrer"</script>';
} else {
$sql = "INSERT INTO user (username, password, email, name) VALUES ('$username', '$passw', '$email', '$name')";
mysqli_query($ConDB, $sql);
$okmsg = "Register with succes.";
mysqli_close($ConDB);//Close conexion.
echo '<script>window.location="#registrer"</script>';
}
}
?>
<a name="registrer"></a>
<form action="" method="POST">
<p><label>name : </label>
<input id="password" type="text" name="name" placeholder="name" /></p>
<?php echo $nameError; ?>
<p><label>User Name : </label>
<input id="username" type="text" name="username" placeholder="username" /></p>
<?php echo $usernameError; ?>
<p><label>E-Mail : </label>
<input id="password" type="email" name="email"/></p>
<?php echo $emailError; ?>
<p><label>Password : </label>
<input id="password" type="password" name="password" placeholder="password" /></p>
<?php echo $passwordError; ?>
<a class="btn" href="login.php">Login</a>
<input class="btn register" type="submit" name="submit" value="Register" />
<?php echo $okmsg; ?>
</form>
您可以尝试使用jqueryajax来满足您的需求
首先，将其添加到您的registration.php文件中
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script>
// when user submit the form
$('form').on('submit', function(event){
$.ajax({
url: "check_username.php",
type: "POST",
dataType: "JSON",
data: {
username: $("#username").val() // get the value from username textbox
},
success: function(data){
if(data.status == "exists"){
alert('Username already existed');
}
else{
$('form').submit();
}
},
});
event.preventDefault();
});
</script>
//当用户提交表单时
$（'form'）。在（'submit'，函数（事件）{
$.ajax({
url:“check_username.php”，
类型：“POST”，
数据类型：“JSON”，
数据：{
用户名：$（“#用户名”）.val（）//从用户名文本框获取值
},
成功：功能（数据）{
如果（data.status==“存在”）{
警报（“用户名已存在”）；
}
否则{
$（'form'）.submit（）；
}
},
});
event.preventDefault（）；
});
现在您的registration.php文件将如下所示
registration.php
姓名：
用户名：
电邮：
密码：
//当用户在“用户名”文本框中键入时
$（'form'）。在（'submit'，函数（事件）{
$.ajax({
url:“check_username.php”，
类型：“POST”，
数据类型：“JSON”，
数据：{
用户名：$（“#用户名”）.val（）//从用户名文本框获取值
},
成功：功能（数据）{
如果（data.status==“存在”）{
警报（“用户名已存在”）；
}
否则{
$（'form'）.submit（）；
}
},
});
event.preventDefault（）；
});
然后创建名为check_username.php的php文件，检查用户提交的用户名是否已存在于数据库中或仍然可用
检查_username.php
下面是它的工作原理：
1.当用户单击register按钮时，jQuery将调用check\u username.php
2.现在在check_username.php中，它将检查数据库中提交的用户名是否已经存在或仍然可用。
3.无论结果是否存在或可用，check_username.php都会将结果发送回registration.php，因为字符串包含“exists”或“available”。
4. registration.php现在获取结果，并将检查由check_username.php发送的结果，如果它包含“exists”或“available”。如果字符串为“存在”，则会触发警报。如果字符串为“可用”，则将提交表单。您可以执行以下操作。首先将用户名设为表中的唯一字段
，然后在插入前检查用户名是否已存在于表中，或者是否未使用选择
查询。谢谢@Anant，但我需要它以消息的形式告诉我用户名正在使用中，以便您以后能告诉他吗checking@Anant这是正确的数字和文字更正，格式化文本
<?php
// Stop header errors
ob_start();
// Check if form has been posted
if (isset($_POST['username'])){
// Requre database connection file
require('connect.php');
// Clean the variables preventing SQL Injection attack
$username = mysqli_real_escape_string($conn, $_POST['username']);
$email = mysqli_real_escape_string($conn, $_POST['email']);
$password = mysqli_real_escape_string($conn, $_POST['password']);
$name = mysqli_real_escape_string($conn, $_POST['name']);
// Check if the username exists
// Construct SELECT query to do this
$sql = "SELECT id FROM user WHERE username = '".$username."';";
$result = mysqli_query($conn, $sql);
$rowsreturned = mysqli_num_rows($result);
// If the username already exists
if ($rowsreturned != 0) {
echo "Username exists, redirecting to register.php with an error GET variable!";
// Redirect user
header('Location: register.php?error=usernametaken');
} else {
// Construct the INSERT INTO query
$sql = "INSERT INTO user (username, password, email, name) VALUES ('".$username."', '".$password."', '".$email."', '".$username."');";
$result = mysqli_query($conn, $sql);
if($result){
// User was inserted
echo "User inserted!";
/* DO WHATEVER YOU WANT TO DO HERE */
} else {
// There was an error inserting
echo "Error inserting, redirecting to register.php with an error GET variable!";
// Redirect user
header('Location: register.php?error=inserterror');
}
}
}
?>
if (isset($_POST['username']) && isset($_POST['password'])){
$username = $_POST['username'];
$email = $_POST['email'];
$password = $_POST['password'];
$name = $_POST['name'];
$query = "select username from user where username = '$username'";
$res = mysql_query($query);
$rows = mysqli_num_rows($res);
if ($rows > 0) {
print 'Username already exists...';
} else {
$query = "INSERT INTO `user` (username, password, email, name) VALUES ('$username', '$password', '$email', '$name')";
$result = mysql_query($query);
if($result){
}
}
}
<?php
//Set empty variables.
$usernameError = $emailError = $passwordError = $nameError = $okmsg = "";
$username = $password = $email = $name = "";
if (isset($_POST['submit'])) {
//Check if empty labels form
if (empty($_POST['name'])) {
$userError = "The 'name' is required.";
echo '<script>window.location="#registrer"</script>';
} else { $name = $_POST['name']; }
if (empty($_POST['email'])) {
$emailError = "El 'Email' es requerido.";
echo '<script>window.location="#registrer"</script>';
} else {
$email = $_POST['email'];
//Check only contain letters and whitespace.
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
$emailError = "El 'Email' is not valid. ";
echo '<script>window.location="#registrer"</script>';
}
}
if (empty($_POST['password'])) {
$passwordError = "The 'password' is requiered.";
echo '<script>window.location="#registrer"</script>';
} else {
$password = $_POST['password'];
}
}
//Check if correctly filled
if ($name && $username && $email && $password) {
require('connect.php');
//Query SQL
$sql = "SELECT * FROM user WHERE username='$username'"; //String SQL
$query = mysqli_query($ConDB, $sql);//Query
//Securite
$username = mysqli_real_escape_string($ConDB, $username);
$password = mysqli_real_escape_string($ConDB, $username);
$passw = sha1($password);//For securite.
$name = mysqli_real_escape_string($ConDB, $username);
$email = mysqli_real_escape_string($ConDB, $username);
if ($existe = mysqli_fetch_object($query)) {
$usernameError = "The 'Username' is already exists.";
echo '<script>window.location="#registrer"</script>';
} else {
$sql = "INSERT INTO user (username, password, email, name) VALUES ('$username', '$passw', '$email', '$name')";
mysqli_query($ConDB, $sql);
$okmsg = "Register with succes.";
mysqli_close($ConDB);//Close conexion.
echo '<script>window.location="#registrer"</script>';
}
}
?>
<a name="registrer"></a>
<form action="" method="POST">
<p><label>name : </label>
<input id="password" type="text" name="name" placeholder="name" /></p>
<?php echo $nameError; ?>
<p><label>User Name : </label>
<input id="username" type="text" name="username" placeholder="username" /></p>
<?php echo $usernameError; ?>
<p><label>E-Mail : </label>
<input id="password" type="email" name="email"/></p>
<?php echo $emailError; ?>
<p><label>Password : </label>
<input id="password" type="password" name="password" placeholder="password" /></p>
<?php echo $passwordError; ?>
<a class="btn" href="login.php">Login</a>
<input class="btn register" type="submit" name="submit" value="Register" />
<?php echo $okmsg; ?>
</form>
--
-- DATA BASE: `user`
--
SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";
CREATE TABLE user (
id int(11) unsigned not null auto_increment primary key,
name varchar(50) not null,
email varchar(80) not null unique,
username varchar(30) not null unique,
password varchar(40) not null
)engine=InnoDB default charset=utf8 collate=utf8_general_ci;
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script>
// when user submit the form
$('form').on('submit', function(event){
$.ajax({
url: "check_username.php",
type: "POST",
dataType: "JSON",
data: {
username: $("#username").val() // get the value from username textbox
},
success: function(data){
if(data.status == "exists"){
alert('Username already existed');
}
else{
$('form').submit();
}
},
});
event.preventDefault();
});
</script>
<form action="" method="POST">
<p>
<label>name : </label>
<input id="password" type="text" name="name" placeholder="name" />
</p>
<p>
<label>User Name : </label>
<input id="username" type="text" name="username" placeholder="username" />
</p>
<p>
<label>E-Mail : </label>
<input id="password" type="email" name="email"/>
</p>
<p>
<label>Password : </label>
<input id="password" type="password" name="password" placeholder="password" />
</p>
<a class="btn" href="login.php">Login</a>
<input class="btn register" type="submit" name="submit" value="Register" />
</form>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script>
// when user typing in 'username' textbox
$('form').on('submit', function(event){
$.ajax({
url: "check_username.php",
type: "POST",
dataType: "JSON",
data: {
username: $("#username").val() // get the value from username textbox
},
success: function(data){
if(data.status == "exists"){
alert('Username already existed');
}
else{
$('form').submit();
}
},
});
event.preventDefault();
});
</script>
<?php
// Check if 'username' textbox is not empty
if(!empty($_POST['username'])){
$username = trim(mysqli_real_escape_string($_POST['username']));
// Check the database if the username exists
$query = "SELECT username FROM `user` WHERE username = '".$username."'";
$result = mysqli_query($query);
if(mysqli_num_rows($result) > 0){
// if username already exist
// insert into array, to be sent to registration.php later
$response['status'] = 'exists';
}
else{
// if username available
$response['status'] = 'available';
}
}
header('Content-type: application/json');
echo json_encode($response);
exit;
?>