c# winform插件

插件接口

namespace IMsg
{
    ///<summary>
    /// 这是插件必须实现的接口，也是主程序与插件通信的唯一接口
    /// 换句话说，主程序只认识插件里的这些方法
    ///</summary>
    public interface IMsgPlug
    {
        /// <summary>
        /// 显示窗体
        /// </summary>
        void OnShowDlg();

        /// <summary>
        /// 显示信息
        /// </summary>
        /// <returns></returns>
        string OnShowInfo();
    }
}

插件1

using IMsg;
using System;

namespace MYPlugin1
{
    public class myConsole : IMsgPlug
    {
        #region IMsgPlug 成员
        public void OnShowDlg()
        {
            Console.WriteLine("控制台调用插件的OnShowDlg方法");
        }
        public string OnShowInfo()
        {
            return "myConsole";
        }
        #endregion
    }
}

插件2

using IMsg;
using System.Windows.Forms;

namespace MYPlugin1
{
    public class MYDlg : Form, IMsgPlug
    {
        #region IMsgPlug 成员

        public void OnShowDlg()
        {
            this.Text = "插件子窗体";
            this.ShowDialog();//调用Form的ShowDialog,显示窗体
        }
        public string OnShowInfo()
        {
            return "MyDlg";
        }
        #endregion
    }
}

winform调用插件

using System;
using System.Collections;
using System.IO;
using System.Reflection;
using System.Windows.Forms;

namespace MsgBoxMain
{
    public partial class FormMain : Form
    {
        ///<summary>
        /// 存放插件的集合
        ///</summary>
        private ArrayList plugins = new ArrayList();
        public FormMain()
        {
            InitializeComponent();
        }

        ///<summary>
        /// 载入所有插件
        ///</summary>
        private void LoadAllPlugs()
        {
            //获取插件目录(plugins)下所有文件夹
            DirectoryInfo dirs = new DirectoryInfo(Application.StartupPath + @"\Plugins");

            foreach (DirectoryInfo dir in dirs.GetDirectories())
            {
                //获取文件夹下文件
                string[] files = Directory.GetFiles(dir.FullName);
                foreach (string file in files)
                {
                    if (file.ToUpper().EndsWith(".DLL"))
                    {
                        try
                        {
                            //载入dll
                            Assembly ab = Assembly.LoadFrom(file);
                            Type[] types = ab.GetTypes();
                            foreach (Type t in types)
                            {
                                //如果某些类实现了预定义的IMsg.IMsgPlug接口，则认为该类适配与主程序(是主程序的插件)
                                if (t.GetInterface("IMsgPlug") != null)
                                {
                                    plugins.Add(ab.CreateInstance(t.FullName));
                                    listBox1.Items.Add(t.FullName);
                                }
                            }
                        }
                        catch (Exception ex)
                        {
                            MessageBox.Show(ex.Message);
                        }
                    }
                }
            }
        }

        private void btnLoadPlug_Click(object sender, EventArgs e)
        {
            LoadAllPlugs();
        }

        //调用插件的方法
        private void btnExecute_Click(object sender, EventArgs e)
        {
            if (this.listBox1.SelectedIndex == -) return;
            object selObj = this.plugins[this.listBox1.SelectedIndex];
            Type t = selObj.GetType();
            MethodInfo OnShowDlg = t.GetMethod("OnShowDlg");
            MethodInfo OnShowInfo = t.GetMethod("OnShowInfo");

            OnShowDlg.Invoke(selObj, null);
            object returnValue = OnShowInfo.Invoke(selObj, null);
            this.lblMsg.Text = returnValue.ToString();

        }
    }
}

界面