php - Ajax调用返回403错误

Question

在我的网站上，我收到了这个Ajax电话：

 //Autocomplete
 $(document).ready(function() {

// Autocomplete for names
$("#search-input-name").keyup(function(){
   $.ajax({
           type: "POST",
           url: "function/autocomplete.php",
           data: {action : "name", keyword: $(this).val()},
           success: function(data){
                    // Actions
           }
           });
 });

 // Autocomplete for cities
 $("#search-input-city").keyup(function(){
    $.ajax({
            type: "POST",
            url: "function/autocomplete.php",
            data: { action: "city", keyword: $(this).val()},
            success: function(data){
                       // Actions
            },
         });
   });
});

此脚本调用此php文件：

<?php
include('db_connect.php');
if (!isset($_POST['action']) && !isset($_POST['keyword'])) {
    echo 'Error';
    die();
} else {
    switch ($_POST['action']):
        case 'name':
            $sql = "SELECT name FROM profiles WHERE name LIKE '" . $_POST['keyword'] . "' ORDER BY name LIMIT 1";
            $results = mysql_query($sql);
            while ($row = mysql_fetch_assoc($results)) {
                $resultset[] = $row;
            }
            if (!empty($resultset)):
 ?>
<ul id="name-list">
    <?php foreach($resultset as $name):?>
        <li onClick="selectName('<?php echo $name["name"]; ?>');"><?php echo $name["name"]; ?></li>
    <?php endforeach;?>
</ul>
 <?php
            endif;
            break;
        case 'city':
            $sql = "SELECT city FROM profiles WHERE city LIKE '" . $_POST['keyword'] . "' ORDER BY city LIMIT 1";
            $results = mysql_query($sql);
            while ($row = mysql_fetch_assoc($results)) {
                $resultset[] = $row;
            }
            if (!empty($resultset)):
?>
<ul id="city-list">
    <?php foreach($resultset as $city):?>
        <li onClick="selectCity('<?php echo $city["city"]; ?>');"><?php echo $city["city"]; ?></li>
    <?php endforeach;?>
</ul>
<?php
            endif;
            break;
    endswitch;
}

脚本运行正常但有时我遇到403错误。 我不知道是否必须更改服务器端的某些配置。

感谢所有帮助