无法解决此问题：致命错误：未捕获异常'PDOException'，消息'SQLSTATE [HY093]：参数号无效：参数未定义'

Question

这是我的代码，它不喜欢我从头文件调用方法的最后一行。它声称无效的参数号，即使我调用的方法采用相同数量的参数。我不明白参数是未定义的部分因为$ params是在调用之前定义的，而$ query是从我的其他文件中传递的值，我应该检查它是否已设置？该文件应该将图像从另一个文件中的表单上传到imgur。

<?php
include_once("connect.php");

    class Image
    {
        public static function uploadImage($formname,$query,$params)
        {

            $formname = "";
            $response = "";
            $image = "";

            if(file_exists($formname))
            {
                $image = base64_encode(file_get_contents($_FILES[$formname]['tmp_name']));
            }
            $options = array('http'=>array(
                'method'=>"POST",
                'header'=>"Authorization: Bearer n/a\n".
                "Content-Type: application/x-www-form-urlencoded",
                'content'=>$image
            ));

            $context = stream_context_create($options);
            $imgurURL = "https://api.imgur.com/3/image";
            if ($_FILES[$formname]['size'] > 10240000) {
                die('Image too big, must be 10MB or less!');
            }
            if(file_exists($formname))
            {
                $response = file_get_contents($imgurURL, false, $context);

            }
            $response = json_decode($response);

            $preparams = array($formname=>$response->data->link);
            $params = $preparams + $params;

            connect::query($query,$params);


        }

    }


?>

 Here's my call to the uploadImage method with the value of $query

$postid = connect::query('SELECT id FROM dry_posts ORDER BY ID DESC LIMIT  1');

Image::uploadImage('postimg', "UPDATE dry_posts SET postimg=:postimg WHERE id=:postid", array(':postid'=>$postid));

这是我的（connect.php）头文件：

<?php
class connect
{

    private static function db()
    {
        $pdo = new PDO('mysql:host=127.0.0.1;dbname=mysql;charset = utf8', 'adereje','Abubba23');
        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        return $pdo;
    }
    public static function query($query,$params = array())
    {

        $statement = self :: db()->prepare($query);
        $statement->execute($params);

        if(explode(' ',$query)[0] == 'SELECT')
        {
            $data = $statement->fetchAll();
            return $data;
        }
    }
}