http://www.cnblogs.com/yjmyzz/archive/2009/12/14/1623396.html
1.为什么要用ActiveX?
网页本身的功能是有限的，要想实现一些网页本身不支持的功能，比如：网页上的p2p视频播放，就得靠ActiveX这种古老的技术。
2.c#能开发ActiveX吗？
严格意义上讲，c#是不能生成纯正ocx控件的，我们在vs.net中新建项目时，也找不到专门的"ActiveX项目"新建项，最多也只就能新 建"类库"得到一个dll而非ocx(因此我们也无法用传统的regsvr32来注册该dll)，但是c#能开发com组件，activeX控件本质上讲 跟com是一类技术，所以用c#开发"能够让网页调用的com类库"还是可行的。
3.开发步骤：
(1)新建一个类库
(2)修改项目的"属性"，在“生成”选项中把“输出”中的“为com互操作注册”勾中，然后再到“应用程序”选项中找到“程序集信息”按钮，点击它，在弹出的界面中勾中“使程序集COM可见(M)”
(3)修改AssemblyInfo.cs，增加[assembly: AllowPartiallyTrustedCallers()]，完整内容类似下面这样:
1 using System.Reflection;
2 using System.Runtime.CompilerServices;
3 using System.Runtime.InteropServices;
4 using System.Security;
5
6 // General Information about an assembly is controlled through the following
7 // set of attributes. Change these attribute values to modify the information
8 // associated with an assembly.
9 [assembly: AssemblyTitle("ActiveXDemo")]
10 [assembly: AssemblyDescription("")]
11 [assembly: AssemblyConfiguration("")]
12 [assembly: AssemblyCompany("Microsoft")]
13 [assembly: AssemblyProduct("ActiveXDemo")]
14 [assembly: AssemblyCopyright("Copyright ? Microsoft 2009")]
15 [assembly: AssemblyTrademark("")]
16 [assembly: AssemblyCulture("")]
17 [assembly: AllowPartiallyTrustedCallers()]
18
19 // Setting ComVisible to false makes the types in this assembly not visible
20 // to COM components. If you need to access a type in this assembly from
21 // COM, set the ComVisible attribute to true on that type.
22 [assembly: ComVisible(true)]
23
24 // The following GUID is for the ID of the typelib if this project is exposed to COM
25 [assembly: Guid("bd585d12-7f22-4b3f-959f-18efbfc53f94")]
26
27 // Version information for an assembly consists of the following four values:
28 //
29 // Major Version
30 // Minor Version
31 // Build Number
32 // Revision
33 //
34 // You can specify all the values or you can default the Build and Revision Numbers
35 // by using the ‘*‘ as shown below:
36 // [assembly: AssemblyVersion("1.0.*")]
37 [assembly: AssemblyVersion("1.0.0.0")]
38 [assembly: AssemblyFileVersion("1.0.0.0")]
(4)新建一个IObjectSafety接口文件IObjectSafety.cs，内容如下:
1 using System;
2 using System.Collections.Generic;
3 using System.Text;
4 using System.Runtime.InteropServices;
5
6 namespace ActiveXDemo
7 {
8 [ComImport, GuidAttribute("CB5BDC81-93C1-11CF-8F20-00805F2CD064")]
9 [InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
10 public interface IObjectSafety
11 {
12 [PreserveSig]
13 int GetInterfaceSafetyOptions(ref Guid riid, [MarshalAs(UnmanagedType.U4)] ref int pdwSupportedOptions, [MarshalAs(UnmanagedType.U4)] ref int pdwEnabledOptions);
14
15 [PreserveSig()]
16 int SetInterfaceSafetyOptions(ref Guid riid, [MarshalAs(UnmanagedType.U4)] int dwOptionSetMask, [MarshalAs(UnmanagedType.U4)] int dwEnabledOptions);
17 }
18
19 }
该内容除命名空间可以更改外，其它内容都是固定的，不要修改
(5)新建一个：Windows Forms-->“用户控件”,我们的主要逻辑就写在这里(还可以在它上面随便放置其它windows常用控件，跟winForm开发一样)，不过首先要修改类定义，让其实现我们刚才定义的接口
1 using System;
2 using System.Runtime.InteropServices;
3 using System.Threading;
4 using System.Windows.Forms;
5
6
7 namespace ActiveXDemo
8 {
9 [Guid("8d7d8518-ca58-4863-b94d-3c616fda7b35")]
10 public partial class MyActiveX : UserControl,IObjectSafety
11 {
12 delegate void D(object obj);
13
14 public MyActiveX()
15 {
16 InitializeComponent();
17 }
18
19 #region IObjectSafety 成员
20
21 private const string _IID_IDispatch = "{00020400-0000-0000-C000-000000000046}";
22 private const string _IID_IDispatchEx = "{a6ef9860-c720-11d0-9337-00a0c90dcaa9}";
23 private const string _IID_IPersistStorage = "{0000010A-0000-0000-C000-000000000046}";
24 private const string _IID_IPersistStream = "{00000109-0000-0000-C000-000000000046}";
25 private const string _IID_IPersistPropertyBag = "{37D84F60-42CB-11CE-8135-00AA004BB851}";
26
27 private const int INTERFACESAFE_FOR_UNTRUSTED_CALLER = 0x00000001;
28 private const int INTERFACESAFE_FOR_UNTRUSTED_DATA = 0x00000002;
29 private const int S_OK = 0;
30 private const int E_FAIL = unchecked((int)0x80004005);
31 private const int E_NOINTERFACE = unchecked((int)0x80004002); 32 33 private bool _fSafeForScripting = true; 34 private bool _fSafeForInitializing = true; 35 36 public int GetInterfaceSafetyOptions(ref Guid riid, ref int pdwSupportedOptions, ref int pdwEnabledOptions) 37 { 38 int Rslt = E_FAIL; 39 40 string strGUID = riid.ToString("B"); 41 pdwSupportedOptions = INTERFACESAFE_FOR_UNTRUSTED_CALLER | INTERFACESAFE_FOR_UNTRUSTED_DATA; 42 switch (strGUID) 43 { 44 case _IID_IDispatch: 45 case _IID_IDispatchEx: 46 Rslt = S_OK; 47 pdwEnabledOptions = 0; 48 if (_fSafeForScripting == true) 49 pdwEnabledOptions = INTERFACESAFE_FOR_UNTRUSTED_CALLER; 50 break; 51 case _IID_IPersistStorage: 52 case _IID_IPersistStream: 53 case _IID_IPersistPropertyBag: 54 Rslt = S_OK; 55 pdwEnabledOptions = 0; 56 if (_fSafeForInitializing == true) 57 pdwEnabledOptions = INTERFACESAFE_FOR_UNTRUSTED_DATA; 58 break; 59 default: 60 Rslt = E_NOINTERFACE; 61 break; 62 } 63 64 return Rslt; 65 } 66 67 public int SetInterfaceSafetyOptions(ref Guid riid, int dwOptionSetMask, int dwEnabledOptions) 68 { 69 int Rslt = E_FAIL; 70 string strGUID = riid.ToString("B"); 71 switch (strGUID) 72 { 73 case _IID_IDispatch: 74 case _IID_IDispatchEx: 75 if (((dwEnabledOptions & dwOptionSetMask) == INTERFACESAFE_FOR_UNTRUSTED_CALLER) && (_fSafeForScripting == true)) 76 Rslt = S_OK; 77 break; 78 case _IID_IPersistStorage: 79 case _IID_IPersistStream: 80 case _IID_IPersistPropertyBag: 81 if (((dwEnabledOptions & dwOptionSetMask) == INTERFACESAFE_FOR_UNTRUSTED_DATA) && (_fSafeForInitializing == true)) 82 Rslt = S_OK; 83 break; 84 default: 85 Rslt = E_NOINTERFACE; 86 break; 87 } 88 89 return Rslt; 90 } 91 92 #endregion 93 94 private void MyActiveX_Load(object sender, EventArgs e) 95 { 96 97 } 98 99 100 public void Start(object obj) 101 {102 for (int i = 0; i < 10; i++)103 {104 Thread t = new Thread(new ParameterizedThreadStart(ShowTime));105 t.Start(obj.ToString() + "，线程：" + i.ToString()); 106 } 107 }108 109 private void button1_Click(object sender, EventArgs e)110 {111 Start("Hello World");112 }113 114 void ShowTime(object obj)115 {116 if (this.listBox1.InvokeRequired)117 {118 D d = new D(DelegateShowTime);119 listBox1.Invoke(d, obj);120 }121 else122 {123 this.listBox1.Items.Add(obj);124 }125 126 127 }128 129 130 void DelegateShowTime(object obj)131 {132 this.listBox1.Items.Add(obj);133 }134 135 136 }137 }
#region IObjectSafety 成员 ... #endregion这一段的内容是固定的，不要修改，其它内容根据自己的业务要求自行修改，另外类前面要加上Guid的标识，以便网页调用时，能用CLSID="xxx"来调用
基本上这样弄完后，就可以在网页中，用类似下面这样的代码来本机调用了：
注意：c#定义的public方法，如果想直接让js调用，只能返回string,DateTime,int,double这一类基本值类型，其它返回类型比如array,object，在js中要么直接报错，要么得到null
1 <object id="x" classid="clsid:8d7d8518-ca58-4863-b94d-3c616fda7b35"></object>
2 <hr />
3 <input type="button" value="调用ActiveX中的多线程方法" onclick="fnTest()" />
4 <script type="text/javascript">
5 var fnTest = function(){
6 var x = document.getElementById("x");
7 x.Start("这是js中的参数");
8 }
9 </script>
4.安装部署
前面已经提到了,c#开发的（伪）"ActiveX"控件并非纯正的ocx，所以只能用RegAsm.Exe
xxx.dll来进行程序集的注册，这里要注意一点：在开发机上，项目编译后vs.net会自动将bin\debug\xxx.dll调用regasm注
册，但在别人机器上就不行了，为了能在调试时模拟其它机器的运行结果，可以在编译后，手动用类似 regAsm.exe
D:\MyDoc\ActiveXDemo\output\ActiveXDemo.dll /u 来反注册(在vs.net命令行模式下)
然后在安装项目上，右键"添加"-->"项目输出"-->"主输出"-->在项目下拉框中选择activex所对应的项目即可.
注意:"主输出来自xxx"的属性栏中，有一个"Register"必须选择"vsdrpCOM"
另外还有一个问题，可能是我机器的个别现象，每次activex项目有修改时，建议最好手动清除安装项目debug目录下的文件，再重新生成安装项目，否则有时候会发现activex修改了，但是安装包中包含的dll还是未修改过的版本。
后话：c#开发的东西是运行于.net 框架之上的，就好比java开发的东西必须要java
runtime才能运行一样，利用本文方法开发出来的dll也必须要安装.net框架才能跑起来，幸好最新的win7中已经集成了.net框架，当然您如
果对于庞大的.net框架安装程序很敏感，仍然觉得纯正的ocx更好的话，建议还是用vb/delphi/c++这一类老牌的开发工具/语言实现。(可以
参考我的另一篇重温delphi之:如何快速开发原生ActiveX控件)
示例源代码下载:http://files.cnblogs.com/yjmyzz/ActiveXDemo.rar