<?php
add_action( 'show_user_profile', 'my_show_extra_profile_fields' );
add_action( 'edit_user_profile', 'my_show_extra_profile_fields' );

function my_show_extra_profile_fields( $user ) {
?>
<script type="text/javascript">
    var form = document.getElementById('your-profile');
    form.encoding = "multipart/form-data";
    form.setAttribute('enctype', 'multipart/form-data');
</script>
<table class="form-table">
    <tr>
        <th><label for="profile_photo">Upload your profile photo</label></th>
        <td>
        <p>
            <input type="file" name="profile_photo" id="profile_photo" />
            <input type="hidden" name="action" value="save">
            <input type="submit" name="submitprofilephoto" id="submitprofilephoto" class="button" value="بارگذاری">
        </p>
            <span class="description">
            <?php
            $author_profile_photo = get_author_profile_photo($user->ID);
            if(is_array($author_profile_photo)):
            ?>
                <a href="<?php echo $author_profile_photo["url"];?>" target="_blank">
                    <img src="<?php echo $author_profile_photo["file"];?>" height="100" width="100" />
                </a>
            <?php
            endif;
            ?>
            </span>
        </td>
    </tr>
</table>

<?php
}

function get_author_profile_photo($user_ID) {

$author_data = get_the_author_meta( 'profile_photo', $user_ID );
$uploads = wp_upload_dir();
$author_data["file"] = $uploads["baseurl"] . $author_data["file"];
return $author_data;
}

add_action( 'personal_options_update', 'my_save_extra_profile_fields' );
add_action( 'edit_user_profile_update', 'my_save_extra_profile_fields' );

function my_save_extra_profile_fields( $user_id ) {

if ( !current_user_can( 'edit_user', $user_id ) )
    return false;

$upload=$_FILES['profile_photo'];
$uploads = wp_upload_dir();
if(isset($_POST) && $_POST['submitprofilephoto']!='') {
    if ($upload['tmp_name'] && file_is_displayable_image( $upload['tmp_name'] )) {

            // handle the uploaded file
            $overrides = array('test_form' => false);
            $file=wp_handle_upload($upload, $overrides);
            $file["file"] = $uploads["subdir"]."/".basename($file["url"]);

            // Setup the array of supported file types. In this case, it's just Images.
            $supported_types = array( 'image/jpeg', 'image/pjpeg', 'image/png' );

            // Get the file type of the upload
            $arr_file_type = wp_check_filetype(basename($upload['name']));
            $uploaded_type = $arr_file_type['type'];

            // Check if the type is supported. If not, throw an error.
            if( $file && in_array($uploaded_type, $supported_types) ) {
                if($upload['size'] > 204800) {
                     wp_die('<strong>ERROR</strong>: Maximum size allowed is 200KB.');
                }

                //remove previous uploaded file
                $author_profile_photo = get_author_profile_photo($user_id);
                @unlink($author_profile_photo["file"]);
                // I even tried unlink without the @ and it still doesn't delete the file!

                update_user_meta( $user_id, 'profile_photo', $file );

        } else wp_die('<strong>ERROR</strong>: Allowd image formats are JPEG, JPG and PNG.');

    } elseif (!file_is_displayable_image( $upload['tmp_name'] )) wp_die('<strong>ERROR</strong>: The file you selected is not an image!');
}
}
?>

function url_to_path_test($url){
    $url=str_replace(rtrim(get_site_url(),'/').'/', ABSPATH, $url);
   return $url;
   }

//remove previous uploaded file
  $author_profile_photo = get_author_profile_photo($user_id);
  $url=str_replace(rtrim(get_site_url(),'/').'/', ABSPATH, $author_profile_photo["file"]);
  @unlink($url);

//remove previous uploaded file
  $author_data = get_the_author_meta( 'profile_photo', $user_id );
  $author_data["file"] = $uploads["path"] . $author_data["file"];

  $imagepath = $author_data["file"];
  @unlink($imagepath);

unlink(public_path('file/to/delete'))

@unlink($author_profile_photo["file"]);