Check if specific input file is empty

In my form I have 3 input fields for file upload:

<input type=file name="cover_image">
<input type=file name="image1">
<input type=file name="image2">

How can I check if cover_image is empty - no file is put for upload?

You can check by using the size field on the $_FILES array like so:

if ($_FILES['cover_image']['size'] == 0 && $_FILES['cover_image']['error'] == 0)
{
    // cover_image is empty (and not an error)
}

(I also check error here because it may be 0 if something went wrong. I wouldn't use name for this check since that can be overridden)

Method 1

if($_FILES['cover_image']['name'] == "") {
// No file was selected for upload, your (re)action goes here
}

Method 2

if($_FILES['cover_image']['size'] == 0) {
// No file was selected for upload, your (re)action goes here
}

You can check if there is a value, and if the image is valid by doing the following:

if(empty($_FILES['cover_image']['tmp_name']) || !is_uploaded_file($_FILES['cover_image']['tmp_name']))
{
   // Handle no image here...
}

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