file_get_contents doesn't work with tmp file - php

Question

My problem: I want to INSERT a image into a MySQL table with BLOB. In the same project I has upload a file but just the link in a VARCHAR column, and it works. Now I tried with file_get_contents and fread and both of them returns empty string. What's wrong with my code? Or is something wrong with the configuration of php.ini? The code is:
$imgdata = NULL;
$imgext = NULL;
$file = $_FILES['foto'];
if (!in_array($file['type'], $con->ext)) {
exit('Archivo no permitido');
} else {
if ($file['error'] === FALSE) {
exit('Error ' . $file['error']);
} else {
$attachtmp = $file['tmp_name'];
$imgext = $file['type'];
if (file_exists($attachtmp)) {
if (is_uploaded_file($attachtmp)) {
$fp = fopen($attachtmp, 'r+b');
$imgdata = fread($fp, filesize($attachtmp));
fclose($fp);
//if (empty(file_get_contents($attachtmp))) {
//$imgdata = $con->real_escape_string(file_get_contents($attachtmp));
//}
} else {
exit('<h3>Error interno del servidor<h3>');
}
} else {
exit('<h3>Error error interno del servidor<h3>');
}
}
}

Answer 1

Check your results first:
// Check $_FILES['foto']['error'] value.
switch ($_FILES['foto']['error']) {
case UPLOAD_ERR_OK:
break;
case UPLOAD_ERR_NO_FILE:
throw new RuntimeException('No file sent.');
case UPLOAD_ERR_INI_SIZE:
case UPLOAD_ERR_FORM_SIZE:
throw new RuntimeException('Exceeded filesize limit.');
default:
throw new RuntimeException('Unknown errors.');
}
taken from php manual