Error with getimagesize in photo upload

Question

I’m trying to set up a system that checks the mime type image when uploading. However.

Follows the code:

<?php 

$action = addslashes(filter_input(INPUT_GET, 'action',FILTER_SANITIZE_SPECIAL_CHARS));

if ((!empty($action)) and ($action == "add")) {
   // Recebe a imagem 
   $imagem = $_FILES["imagem"];

   $size = getimagesize($imagem); 

   switch ($size['mime']) { 
       case "image/gif": 
           echo "Image is a gif"; 
           break; 
       case "image/jpeg": 
           echo "Image is a jpeg"; 
           break; 
       case "image/png": 
           echo "Image is a png"; 
           break; 
       case "image/bmp": 
           echo "Image is a bmp"; 
           break; 
   } 
}

?>

<form name='form' method='post' action='?action=add' enctype='multipart/form-data'>
    <input type="file" name="imagem">
    <input type="submit" value="ok">
</form>

Error log:

Warning: getimagesize() expects Parameter 1 to be string, array Given in /Library/Webserver/Documents/teste.php on line 12

Error occurs on this line:

$size = getimagesize($imagem); 

I modified it to

$image = $_FILES['image']['tmp_name'];

But returns error in getimagesize(). "Parameter cannot be Empty"

Answer 1

In this section of the original code,

$imagem = $_FILES["imagem"];

Modify to

$imagem = $_FILES['imagem']['tmp_name'];

The above example is considering an image only.
Multiple image upload requires a different treatment.

If you have questions about which indexes are in the array, do a print_r($_FILES); exit;. Then you can see the structure.

To give more consistency in switch()

 case "image/jpeg": 
       echo "Image is a jpeg"; 
       break;

Change to

 case "image/jpeg":
 case "image/pjpeg":
 case "image/jpg":
 case "image/pjpg":
       echo "Image is a jpeg"; 
       break; 

The reason is that jpg can come with one of these 4 formats.

Another point that needs to be more consistent is to check if the image exists before trying to use it.

if (file_exists($imagem)) {
    $size = getimagesize($imagem); 
} else {
    // dispara um exception, seta um código de erro.. enfim, o que vc preferir
}

There are many other details. I just showed the most obvious and simple.

_{The examples are purely didactic.}