问如何使用dll中的函数？

EN

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using ClouReaderAPI;
using ClouReaderAPI.ClouInterface;
using ClouReaderAPI.Models;
using System.IO.Ports;

namespace HopeLand_Lucas_WindowsForms
{
public partial class Form1 : Form
{
    Form exemplo = new Form();
    static Param_Set param_Set = new Param_Set();
    static RFID_Option rfid_Option = new RFID_Option();
    String ConnID = "COM12:115200";

    public Form1()
    {
        InitializeComponent();
        getAvailablePorts();

        {

            if (ClouReaderAPI.CLReader.CreateSerialConn(ConnID, exemplo))
            { 

            }

        }
    }