<form class="form-horizontal" method="post" enctype="multipart/form-data" action="?">
<input type="file" name="logo" class="form-control" id="inputFile" required>
<input type="submit" class="btn btn-success" value="Add">
</form>
<?php
if(isset($_FILES))
{
echo '<pre>';
print_r($_FILES);
echo '</pre>';
}
[logo] => Array
(
[name] => 2-4-6.png
[type] =>
[tmp_name] =>
[error] => 6
[size] => 0
)