如何将这些代码放入WordPress中的function.php？

Question

我想将带有中文字符的文件上传到WordPress网站。但是，该文件的名称是乱码。我搜索了这个问题并找到了一些解决方案。一种是修改//wp-admin/includes/file.php

    function wp_handle_upload( &$file, $overrides = false, $time = null ) {
//….
// Move the file to the uploads dir
//$new_file = $uploads['path'] . “/$filename”;
$new_file = $uploads['path'] . “/” . iconv(“UTF-8″,”GB2312″,$filename);
//…
//return apply_filters( ‘wp_handle_upload’, array( ‘file’ => $new_file, ‘url’ => $url, ‘type’ => $type ), ‘upload’ );
return apply_filters( ‘wp_handle_upload’, array( ‘file’ => $uploads['path'] . “/$filename”, ‘url’ => $url, ‘type’ => $type ) , ‘upload’);
}

据我所知，它改变了文件名的编码。但我想将它放在主题文件夹中的function.php中。我该怎么办？