这些代码始终提示无效的路径文件.我不知道为什么:/

<?php
if(isset($_POST['sportname'])){ 
    include("connect.php");
    $name = $_POST['sportname'];
    $sql = "Select docs From tbl_sport WHERE sprt_name= '".$name."'";
    $result = mysql_query($sql);
    $row=mysql_fetch_object($result);
    $file = $row->docs; 

    ini_set("allow-url-fopen", true);
    // Fetch the file info.
    $filePath = 'http://prisaa-region11.com/Docs/'.$file;
    if(file_exists($filePath)) {
        $fileName = basename($filePath);
        $fileSize = filesize($filePath);
        // Output headers.
        header("Cache-Control: private");
        header("Content-Type: application/stream");
        header("Content-Length: ".$fileSize);
        header("Content-Disposition: attachment; filename=".$fileDisplayName);
        // Output file.
        readfile ($filePath);                   
        exit();
    }
    else {
        die('The provided file path is not valid.');
    }
}       
?>

我不知道这条路有什么问题