在用户名可用性检查中，我创建了两个页面:register.php和registerControl.php，对其进行控制。 我检查数据库连接是否正常。 以前在一个php页面上创建的所有内容（所有语句，insertin data into db）。 但是当ajax验证其他输入时，它会复制html内容并显示其中的错误，而不是在单个html元素中显示错误消息。
所以我把它分成两个页面，但是现在ajax没有显示任何错误并响应。 以下是我的作品:
RegisterControl.php
<?php
require('../includes/config.php');
if(isset($_POST['username'])){
//username validation
$username = $_POST['username'];
if (! $user->isValidUsername($username)){
$infoun[] = 'Your username must be at least 6 alphanumeric characters';
} else {
$stmt = $db->prepare('SELECT username FROM members WHERE username = :username');
$stmt->execute(array(':username' => $username));
$row = $stmt->fetch(PDO::FETCH_ASSOC);
if (! empty($row['username'])){
$errorun[] = 'This username already in use';
}
}
}
?>
register.php
<script type="text/javascript">
$(document).ready(function(){
$("#username").keyup(function(event){
event.preventDefault();
var username = $(this).val().trim();
if(username.length >= 3){
$.ajax({
url: 'registercontrol.php',
type: 'POST',
data: {username:username},
success: function(response){
// Show response
$("#uname_response").html(response);
}
});
}else{
$("#uname_response").html("");
}
});
});
</script>
<form id="register-form" class="user" role="form" method="post" action="registercontrol.php" autocomplete="off">
<input type="text" name="username" id="username" class="form-control form-control-user" placeholder="Username" value="<?php if(isset($error)){ echo htmlspecialchars($_POST['username'], ENT_QUOTES); } ?>" tabindex="2" required>
<div id="uname_response" ></div>
</form>
我们需要在RegisterControl.php中打印响应，这样我们就可以在您的Register.php中获得响应。
按以下方式更改代码
<?php
require('../includes/config.php');
if(isset($_POST['username'])){
//username validation
$username = $_POST['username'];
if (! $user->isValidUsername($username)){
echo 'Your username must be at least 6 alphanumeric characters';
} else {
$stmt = $db->prepare('SELECT username FROM members WHERE username = :username');
$stmt->execute(array(':username' => $username));
$row = $stmt->fetch(PDO::FETCH_ASSOC);
if (! empty($row['username'])){
echo 'This username already in use';
}
}
}
?>
您需要从RegisterControl.php返回或回显一些内容。
<?php
require('../includes/config.php');
if(isset($_POST['username'])){
//username validation
$username = $_POST['username'];
if (! $user->isValidUsername($username)){
$infoun[] = 'Your username must be at least 6 alphanumeric characters';
echo json_encode($infoun);
exit;
} else {
$stmt = $db->prepare('SELECT username FROM members WHERE username = :username');
$stmt->execute(array(':username' => $username));
$row = $stmt->fetch(PDO::FETCH_ASSOC);
if (! empty($row['username'])){
$errorun[] = 'This username already in use';
echo json_encode($errorun);
exit;
}
echo $row[username];
exit;
}
}
?>
