请在主题函数中添加以下代码。php文件：

add_filter( \'wp_check_filetype_and_ext\', \'file_and_ext_allow_for_user\', 10, 4 );
function file_and_ext_allow_for_user( $types, $file, $filename, $mimes )
{
    if( false !== strpos( $filename, \'.doc\' ) ) {
        $types[\'ext\'] = \'doc\';
        $types[\'type\'] = \'application/msword\';
    } else if( false !== strpos( $filename, \'.pdf\' ) ) {
        $types[\'ext\'] = \'pdf\';
        $types[\'type\'] = \'application/pdf\';
    } else if( false !== strpos( $filename, \'.docx\' ) ) {
        $types[\'ext\'] = \'docx\';
        $types[\'type\'] = \'application/docx\';
    }
    return $types;
}

if ( ! function_exists( \'wp_handle_upload\' ) ) {
    require_once( ABSPATH . \'wp-admin/includes/file.php\' );
}

$uploadedfile = $_FILES[\'amfile\'];

if( $uploadedfile ){

    $u = "Uploaded file set";

    $upload_overrides = array( \'test_form\' => false );

    $movefile = wp_handle_upload( $uploadedfile, $upload_overrides ); 

    if ( $movefile && !isset( $movefile[\'error\'] ) ) {

        $m = "Movefile file set";

        echo "File is valid, and was successfully uploaded.\\n";
        var_dump( $movefile);

    } else {
        $m = "Movefile file NOT set";
        /**
         * Error generated by _wp_handle_upload()
         * @see _wp_handle_upload() in wp-admin/includes/file.php
         */
        print_r($movefile);
        $error = $movefile[\'error\'];
    }


} else  {
    $u = "Uploaded file NOT set";
} 

echo $u . "<br>";
echo $m . "<br>";
echo $error . "<br>";