Codeigniter “file_exists($filename)”

问题:

Need help with the codeigniter, I think file_exists is for server path, not for url. but my image folder got same level with application and system folder. find nothing on google, please help

$url=base_url();
$filename="$url/upload/$id.jpg";
if (file_exists($filename)){
    echo "<li><img src=\"".$url."upload/$id.jpg\" width=\"40\" height=\"40\" /></li>";
}else{
    echo "<li><img src=\"http://www.mydomain.com/haha/image/noimg.png\" width=\"40\" height=\"40\" /></li>";
}

回答1:

Codeigniter is always running on index.php, so all paths are relative from there. You can use any of the following, assuming upload/ is at the same level as index.php:

• file_exists("upload/$id.jpg")

• file_exists("./upload/$id.jpg")

• file_exists(FCPATH."upload/$id.jpg")

FCPATH is a constant that Codeigniter sets which contains the absolute path to your index.php.

As a side note, I prefer is_file() when checking files, as file_exists() returns true on directories. In addition, you might want to see if getimagesize() returns FALSE to make sure you have an image.