玄铁剑

　昨天晚上花了一晚上时间写了一个从程序集中动态加载窗体的程序．将任何包含窗体的代码编译成 dll 文件，再把 dll 文件拷贝到本程序的目录下，本程序运行时即可动态检查到 dll 文件中的窗体，将窗体类的类型在程序菜单中显示出来，点击菜单即可运行对应的窗体．

　　本程序主要用到了 Assembly 类动态加载程序集，再得到程序集中包含类的 Type 类型，动态生成类实例，动态调用类方法．个人觉得这是一种提供高度松耦合，可随意扩展的程序结构框架，希望和大家探讨一下这种框架的应用前景！

　　关键性代码如下：
 using System;
 using System.Drawing;
 using System.IO;
 using System.Reflection;
 using System.Collections;
 using System.ComponentModel;
 using System.Windows.Forms;
 using System.Data;
 
 namespace WindowsFormTest
   {
      /// <summary>
     /// Form1 的摘要说明。
     /// </summary>
     public class FrmMain : System.Windows.Forms.Form
       {
         private int formNum;
         private ArrayList formTypes = new ArrayList();
         private ArrayList formObjects = new ArrayList();
 
         private System.Windows.Forms.MainMenu mnuMain;
         private System.Windows.Forms.MenuItem mnuItmRun;
         private System.Windows.Forms.MenuItem mnuItemWindow;
         private System.Windows.Forms.MenuItem mnuItmHelp;
         private System.Windows.Forms.MenuItem mnuItmCascade;
         private System.Windows.Forms.MenuItem mnuItmTileHorizontal;
         private System.Windows.Forms.MenuItem mnuItmTileVertical;
         private System.Windows.Forms.MenuItem menuItem1;
         private System.Windows.Forms.MenuItem mnuItmAbout;
         private System.Windows.Forms.StatusBar staBarMain;
         private System.Windows.Forms.StatusBarPanel pnlInfo;
         private System.Windows.Forms.StatusBarPanel pnlNum;
          /// <summary>
         /// 必需的设计器变量。
         /// </summary>
         private System.ComponentModel.Container components = null;
 
         public FrmMain()
           {
             //
             // Windows 窗体设计器支持所必需的
             //
             InitializeComponent();
 
             //
             // TODO: 在 InitializeComponent 调用后添加任何构造函数代码
             //
         }
 
          /// <summary>
         /// 清理所有正在使用的资源。
         /// </summary>
         protected override void Dispose( bool disposing )
           {
             if( disposing )
               {
                 if (components != null) 
                   {
                     components.Dispose();
                 }
             }
             base.Dispose( disposing );
         }
 
          Windows 窗体设计器生成的代码                                                                                                                                
 
         private void FrmMain_Load(object sender, System.EventArgs e)
           {
             Assembly assembly = null;
             string windowsPath = Path.Combine(Application.StartupPath, "Windows");
 
             foreach (string dllFile in Directory.GetFiles(windowsPath, "*.dll"))
               {
                 assembly = Assembly.LoadFile(dllFile);
                 Type[] types = assembly.GetTypes();
                 
                 foreach (Type t in types)
                   {
                     if (t.BaseType == typeof(Form))
                       {
                         this.formTypes.Add(t);
                         MenuItem item = this.mnuItmRun.MenuItems.Add(t.FullName);
                         item.Click += new EventHandler(menuItemNewItem_Click);
                     }
                 }
             }
         }
 
         private void menuItemNewItem_Click(object sender, EventArgs e)
           {
             MenuItem item = (MenuItem)sender;
 
             Type t = (Type)(this.formTypes[item.Index]);
 
             Object obj = Activator.CreateInstance(t);
             this.formObjects.Add(obj);
             formNum += 1;
 
              t.InvokeMember("MdiParent", BindingFlags.SetProperty, null, obj, new object[]  {this});
              t.InvokeMember("Text", BindingFlags.SetProperty, null, obj, new object[]  {t.FullName+"  窗体："+formNum});
              t.InvokeMember ("Show", BindingFlags.InvokeMethod, null, obj, new object []  {});
 
             ((Form)obj).Closing += new CancelEventHandler(FrmWindow_Closing);
             ((Form)obj).Activated += new EventHandler(FrmWindow_Activated);
             MenuItem menuItem = this.mnuItemWindow.MenuItems.Add(((Form)obj).Text);
             menuItem.Click += new EventHandler(menuItemWindow_Click);
 
             this.pnlNum.Text = "当前装载了"+this.formObjects.Count+"个窗体";
             this.pnlInfo.Text = "当前活动窗体："+this.ActiveMdiChild.Text;
         }
 
         private void menuItemWindow_Click(object sender, System.EventArgs e)
           {
             MenuItem item = (MenuItem)sender;
 
             ((Form)(this.formObjects[item.Index-4])).Activate();
 
             this.pnlNum.Text = "当前装载了"+this.formObjects.Count+"个窗体";
             this.pnlInfo.Text = "当前活动窗体："+this.ActiveMdiChild.Text;
         }
 
         private void FrmWindow_Activated(object sender, System.EventArgs e)
           {
             this.pnlNum.Text = "当前装载了"+this.formObjects.Count+"个窗体";
             this.pnlInfo.Text = "当前活动窗体："+this.ActiveMdiChild.Text;
         }
 
         private void FrmWindow_Closing(object sender, System.ComponentModel.CancelEventArgs e)
           {
             for (int i=0; i<this.formObjects.Count; i++)
               {
                 if (((Form)this.formObjects[i]).Text == ((Form)sender).Text)
                   {
                     this.formObjects.RemoveAt(i);
                     this.mnuItemWindow.MenuItems.RemoveAt(i+4);
 
                     this.pnlNum.Text = "当前装载了"+this.formObjects.Count+"个窗体";
                     this.pnlInfo.Text = "当前活动窗体："+this.ActiveMdiChild.Text;
                     break;
                 }
             }
         }
 
         private void mnuItmCascade_Click(object sender, System.EventArgs e)
           {
             this.LayoutMdi(MdiLayout.Cascade);
         }
 
         private void mnuItmTileHorizontal_Click(object sender, System.EventArgs e)
           {
             this.LayoutMdi(MdiLayout.TileHorizontal);
         }
 
         private void mnuItmTileVertical_Click(object sender, System.EventArgs e)
           {
             this.LayoutMdi(MdiLayout.TileVertical);
         }
 
         private void mnuItmAbout_Click(object sender, System.EventArgs e)
           {
             new FrmAbout().ShowDialog(this);
         }
    }
 }
 
程序源码下载：http://www.cnblogs.com/Files/Infinity/WindowsForm.rar