请看这个，它对我来说很好：）

function uop_login_redirect( $redirect_to, $request, $user  ) {
    return ( is_array( $user->roles ) && in_array( \'administrator\', $user->roles ) ) ? admin_url() : site_url();
}
add_filter( \'login_redirect\', \'uop_login_redirect\', 10, 3 );

I use this:

// redirecting to chosen language dashboard 
add_filter( \'login_redirect\', \'admin_redirect\', 10, 3 );    //
function admin_redirect( $redirect_to, $request, $user ) {
    if(isset($_POST[\'redirect_to\']) && $_POST[\'redirect_to\']==network_home_url().\'wp-admin/\') {
        //is there a user to check?
        if ( isset( $user->roles ) && is_array( $user->roles ) ) {
            return network_home_url().\'eng/wp-admin\';
        }
    }
    else { return $redirect_to; }
}