如果图像已经存在，请使用PHP重命名图像

Question

I'm working on a system that uses images, and the images are named by a md5-ed email. And I'd like to add a -1 -2 etc after the newly uploaded image if an image with the md5-ed email name already exists. Here's my code:

    public function upload() {  

    global $email;

    $fileName = $_FILES['userfile']['name'];
    $tmpName  = $_FILES['userfile']['tmp_name'];
    $fileSize = $_FILES['userfile']['size'];
    $fileType = $_FILES['userfile']['type'];
    $user     = $_SESSION['user'];

    $fp      = fopen($tmpName, 'r');
    $content = fread($fp, filesize($tmpName));
    $content = addslashes($content);
    fclose($fp);

    if(!get_magic_quotes_gpc()) {
        $fileName = addslashes($fileName);
    }

    $new_file_name = md5($email);


    $fileExists = file_exists("../lib/uploads/" . $new_file_name);

    $query = mysql_query("SELECT * FROM avatars WHERE ( name='$fileName' ) OR ( name='$new_file_name' ) ");

    $num_rows = mysql_num_rows($query);


    if ( $fileExists ) {

        $fileName = $new_file_name; 
        $first = 1;
        $separator = '-';

        while ( file_exists("../lib/uploads/" . $fileName) ) {

            preg_match('/(.+)'.$separator.'([0-9]+)$/', $fileName, $match);     

            $new_file_name = isset($match[2]) ? $match[1].$separator.($match[2] + 1) :$fileName.$separator.$first;

            $first++;   

        }

        $fileName = $new_file_name;

    } elseif ( empty( $fileName ) ) {

        echo '<div class="error">Please Select a file first.</div>';

    } else {

        move_uploaded_file($_FILES["userfile"]["tmp_name"],
          "lib/avatars/" . $fileName);

        echo "<div class='success'>File $fileName Uploaded.</div>";  

    }

} // ends upload() function

But I don't know what's wrong, it uploads the image with it's original name. Not even with the md5-ed email as name.

Answer 1

In short

You've messed up your if statements .

In detail

This is very veryu very simple. In your last else (the one that executes when the file doesnt exist) you have

move_uploaded_file($_FILES["userfile"]["tmp_name"],
      "lib/avatars/" . $fileName);

But if you trace back, you will see that $fileName is set to

$fileName = $_FILES['userfile']['name'];

and not the md5 of the email. You have to remove the final else condition and have its code execute EVERY time. Of course as long as the $fileName is not empty.

So your code should be:

if ( $fileExists ) {

    $fileName = $new_file_name; 
    $first = 1;
    $separator = '-';

    while ( file_exists("../lib/uploads/" . $new_file_name ) ) {

        preg_match('/(.+)'.$separator.'([0-9]+)$/', $new_file_name, $match);    

        $new_file_name = isset($match[2]) ? $match[1].$separator.($match[2] + 1) :$new_file_name.$separator.$first;      
        $first++;   

    }
} 

// <----
// Moved this one outside, since it always executes
// ---->
$fileName = $new_file_name;

// <----
// Separated this if, since it has nothing to do with the above
// ---->
if ( empty( $fileName ) ) {

    echo '<div class="error">Please Select a file first.</div>';

} else {

    move_uploaded_file($_FILES["userfile"]["tmp_name"],
      "lib/avatars/" . $fileName);

    echo "<div class='success'>File $fileName Uploaded.</div>";  

}

} // ends upload() function

How you can optimize it

This depends if you are expecting single users to have lot's of images. If this is NOT the case, then leave it as is.

Otherwise, you will quickly end up having to wait for a long time after uploading 10th, 20th photo.

One way to improve it would be to search for files in a directory that fit a pattern (in this case your md5). For example like this:

foreach (glob($md5 . "*") as $filename) {
    echo "$filename size " . filesize($filename) . "\n";
}

This way you instantly know if there are already files with this md5 and how many of them.