从 dll 程序集中动态加载窗体

转载：http://www.cnblogs.com/Infinity/archive/2006/10/26/540347.html 感谢原作者。

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#region Windows 窗体设计器生成的代码
/**//// <summary>
/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
/// </summary>
private void InitializeComponent()
{
this.mnuMain = new System.Windows.Forms.MainMenu();
this.mnuItmRun = new System.Windows.Forms.MenuItem();
this.mnuItemWindow = new System.Windows.Forms.MenuItem();
this.mnuItmCascade = new System.Windows.Forms.MenuItem();
this.mnuItmTileHorizontal = new System.Windows.Forms.MenuItem();
this.mnuItmTileVertical = new System.Windows.Forms.MenuItem();
this.menuItem1 = new System.Windows.Forms.MenuItem();
this.mnuItmHelp = new System.Windows.Forms.MenuItem();
this.mnuItmAbout = new System.Windows.Forms.MenuItem();
this.staBarMain = new System.Windows.Forms.StatusBar();
this.pnlInfo = new System.Windows.Forms.StatusBarPanel();
this.pnlNum = new System.Windows.Forms.StatusBarPanel();
((System.ComponentModel.ISupportInitialize)(this.pnlInfo)).BeginInit();
((System.ComponentModel.ISupportInitialize)(this.pnlNum)).BeginInit();
this.SuspendLayout();
//
// mnuMain
//
this.mnuMain.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
this.mnuItmRun,
this.mnuItemWindow,
this.mnuItmHelp});
//
// mnuItmRun
//
this.mnuItmRun.Index = 0;
this.mnuItmRun.Text = "运行窗体(&R)";
//
// mnuItemWindow
//
this.mnuItemWindow.Index = 1;
this.mnuItemWindow.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
this.mnuItmCascade,
this.mnuItmTileHorizontal,
this.mnuItmTileVertical,
this.menuItem1});
this.mnuItemWindow.Text = "窗口(&W)";
//
// mnuItmCascade
//
this.mnuItmCascade.Index = 0;
this.mnuItmCascade.Text = "层叠窗口";
this.mnuItmCascade.Click += new System.EventHandler(this.mnuItmCascade_Click);
//
// mnuItmTileHorizontal
//
this.mnuItmTileHorizontal.Index = 1;
this.mnuItmTileHorizontal.Text = "横向平铺窗口";
this.mnuItmTileHorizontal.Click += new System.EventHandler(this.mnuItmTileHorizontal_Click);
//
// mnuItmTileVertical
//
this.mnuItmTileVertical.Index = 2;
this.mnuItmTileVertical.Text = "纵向平铺窗口";
this.mnuItmTileVertical.Click += new System.EventHandler(this.mnuItmTileVertical_Click);
//
// menuItem1
//
this.menuItem1.Index = 3;
this.menuItem1.Text = "-";
//
// mnuItmHelp
//
this.mnuItmHelp.Index = 2;
this.mnuItmHelp.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
this.mnuItmAbout});
this.mnuItmHelp.Text = "帮助(&H)";
//
// mnuItmAbout
//
this.mnuItmAbout.Index = 0;
this.mnuItmAbout.Shortcut = System.Windows.Forms.Shortcut.F1;
this.mnuItmAbout.Text = "关于(&A)";
this.mnuItmAbout.Click += new System.EventHandler(this.mnuItmAbout_Click);
//
// staBarMain
//
this.staBarMain.Location = new System.Drawing.Point(0, 343);
this.staBarMain.Name = "staBarMain";
this.staBarMain.Panels.AddRange(new System.Windows.Forms.StatusBarPanel[] {
this.pnlInfo,
this.pnlNum});
this.staBarMain.ShowPanels = true;
this.staBarMain.Size = new System.Drawing.Size(584, 22);
this.staBarMain.TabIndex = 1;
//
// pnlInfo
//
this.pnlInfo.Width = 300;
//
// pnlNum
//
this.pnlNum.AutoSize = System.Windows.Forms.StatusBarPanelAutoSize.Spring;
this.pnlNum.Width = 268;
//
// FrmMain
//
this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
this.ClientSize = new System.Drawing.Size(584, 365);
this.Controls.Add(this.staBarMain);
this.IsMdiContainer = true;
this.Menu = this.mnuMain;
this.Name = "FrmMain";
this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
this.Text = "动态加载窗体";
this.Load += new System.EventHandler(this.FrmMain_Load);
((System.ComponentModel.ISupportInitialize)(this.pnlInfo)).EndInit();
((System.ComponentModel.ISupportInitialize)(this.pnlNum)).EndInit();
this.ResumeLayout(false);

}
#endregion

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：/Files/Infinity/WindowsForm.rar
　　
　　程序截图：

单个 dll 文件包含一个窗体时：

当程序目录下的所有程序集中包含一个窗体类时，程序运行界面：


多个 dll 文件包含多个窗体时：

当程序目录下的所有程序集中包含多个窗体类时，程序运行界面：