为完成网页自动下载并安装控件的功能,需要通过C#创建一个ActiveX控件,然后将该控件置于安装程序中,在打开网页的时候下载、安装并注册该ActiveX控件。本文是采用VS2005创建的,VS2003创建过程与之相似。
首先,创建一个类库,为其命名为CreateActiveXEmail:
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删除掉默认生成的类Class1.cs,创建一个接口ActiveXEmailInterface:
using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;
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namespace CreateActiveXEmail
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...{
[Guid("CB5BDC81-93C1-11CF-8F20-00805F2CD064"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface ActiveXEmailInterface
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...{
void GetInterfacceSafyOptions(int riid, out int pdwSupportedOptions, out int pdwEnabledOptions);
void SetInterfaceSafetyOptions(int riid, int dwOptionsSetMask, int dwEnabledOptions);
}
}
其中GUID可以通过【工具】-【创建GUID】来产生。
实现该接口的目的就是提高程序的安全性,以便客户端IE在不更改设置的情况下可以预行该ActiveX控件。
然后,用你需要实现某些功能的类来继承上面的接口。
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
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namespace CreateActiveXEmail
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...{
[Guid("060d1308-f34e-4c9f-8962-0abafe385d33"), ComVisible(true)]
public class ActiveXEmail : ActiveXEmailInterface
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...{
public void GetInterfacceSafyOptions(int riid, out int pdwSupportedOptions, out int pdwEnabledOptions)
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...{
pdwSupportedOptions = 1;
pdwEnabledOptions = 2;
}
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public void SetInterfaceSafetyOptions(int riid, int dwOptionsSetMask, int dwEnabledOptions)
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...{
}
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public ActiveXEmail()
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...{
}
}
}
注意,上面代码中的类属性“ComVisible(true)”,是必须添加的。
在上面的类中,仅仅是现实了接口的两个方法,至于其他需要的方法,自行添加即可。另外,需要对项目属性进行一点修改:
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注意,类属性中的“ComVisible(true)”和上图中的【为 COM Interop 注册】缺一不可!只有这样才能生成tlb文件。
这样,一个可用的ActiveX控件就已经生成。在本机你可以随意调用其中的任何方法,但问题是,当客户端机器需要远程调用时,必须在能在客户端机器上注册该ActiveX控件才行。所以,还必须进行下面的步骤:将该ActiveX打包,在安装后在目标机器进行注册。
创建一个安装包:
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然后右键单击项目,点击【添加】-【项目输出】,在【主输出】中选择上面创建的工程“CreateActiveXEmail”。然后,打开安装工程的【属性】页面,对项目的【安装URL】项进行设置:
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注意,上图的【安装URL】项中,必须使用绝对路径。另外,上图中的“DllFolder”是一个已发布网站“http://172.16.11.136/TestingAX”下的一个目录,这意味着,当在客户端访问页面时,如果客户端未安装当前ActiveX控件,则从路径http://172.16.11.136/TestingAX/DllFolder”来下载。
最后,在页面中按如下方法调用即可:
<object classid="clsid:060d1308-f34e-4c9f-8962-0abafe385d33"
codebase="DllFolder/setup.exe#version=1,0,0,0"></object>
另外,还可以采用其他方法,即上面的类库属性不选择【为 COM Interop 注册】,安装工程属性不为【安装URL】指定路径,类中也不添加“ComVisible(true)”属性,而是创建一个安装类:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Configuration.Install;
using System.Reflection;
using System.IO;
using Microsoft.Win32;
using System.Diagnostics;
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namespace CreateActiveXEmail
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...{
[RunInstaller(true)]
public partial class CustomInstaller : Installer
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...{
private string regCommandFile = string.Empty;
private string unRegCommandFile = string.Empty;
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public CustomInstaller()
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...{
InitializeComponent();
}
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protected override void OnAfterInstall(System.Collections.IDictionary savedState)
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...{
base.OnAfterInstall(savedState);
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try
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...{
//get the path of the Regasm.exe
string regasmPath = string.Empty;
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//get the path of the current executing assembly
string currentAsmDLLFilePath = Assembly.GetExecutingAssembly().Location;
string currentAsmPath = currentAsmDLLFilePath.Substring(0, currentAsmDLLFilePath.LastIndexOf('\') + 1);
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string currentRegasmPath = string.Format("{0}{1}", currentAsmPath, "RegAsm.exe");
if (!File.Exists(currentRegasmPath))
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...{
try
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...{
RegistryKey frmReg = Registry.LocalMachine.OpenSubKey(@"SOFTWAREMicrosoft.NETFramework");
if (frmReg == null)
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...{
//the .net framework do not exist in the local machine
return;
}
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string frameworkVersion = Environment.Version.ToString();
frameworkVersion = frameworkVersion.Substring(0, frameworkVersion.LastIndexOf('.'));
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regasmPath = string.Format(@"{0}v{1}{2}", frmReg.GetValue("InstallRoot").ToString(), frameworkVersion, "RegAsm.exe");
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if (!File.Exists(regasmPath))
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...{
//the Regasm.exe do not exist in the local machine
return;
}
}
catch (System.ArgumentException ex)
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...{
throw new System.ArgumentException(ex.Message);
}
}
else
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...{
regasmPath = currentRegasmPath;
}
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//create the registration command line
string regCommand = string.Format("{0} "{1}" /{2} /{3}", regasmPath, currentAsmDLLFilePath, "tlb", "codebase");
try
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...{
regCommandFile = string.Format("{0}{1}", currentAsmPath, "Regasm.bat");
if (File.Exists(regCommandFile))
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...{
File.Delete(regCommandFile);
}
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using (StreamWriter swReg = File.CreateText(regCommandFile))
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...{
swReg.Write(regCommand);
swReg.Flush();
}
}
catch (UnauthorizedAccessException uaex)
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...{
throw new UnauthorizedAccessException(uaex.Message);
}
catch (DirectoryNotFoundException dnex)
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...{
throw new DirectoryNotFoundException(dnex.Message);
}
catch (IOException ioex)
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...{
throw new IOException(ioex.Message);
}
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//create the unregistration command file
string unRegCommand = string.Format("{0} "{1}" /{2}", regasmPath, currentAsmDLLFilePath, "u");
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try
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...{
unRegCommandFile = string.Format("{0}{1}", currentAsmPath, "UnRegasm.bat");
if (File.Exists(unRegCommandFile))
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...{
File.Delete(unRegCommandFile);
}
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using (StreamWriter swReg = File.CreateText(unRegCommandFile))
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...{
swReg.Write(unRegCommand);
swReg.Flush();
}
}
catch (UnauthorizedAccessException uaex)
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...{
throw new UnauthorizedAccessException(uaex.Message);
}
catch (DirectoryNotFoundException dnex)
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...{
throw new DirectoryNotFoundException(dnex.Message);
}
catch (IOException ioex)
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...{
throw new IOException(ioex.Message);
}
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//register for the COM Interop
Process.Start(regCommandFile);
}
catch (Exception ex)
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...{
throw new Exception(ex.Message);
}
}
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public override void Uninstall(System.Collections.IDictionary savedState)
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...{
try
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...{
Process.Start(unRegCommandFile);
}
catch (Exception ex)
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...{
throw new Exception(ex.Message);
}
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base.Uninstall(savedState);
}
}
}
因为没有了“ComVisible(true)”和【为 COM Interop 注册】,工程也就无法生成tlb文件,没有tlb文件也就意味着注册失败,dll文件或ActiveX控件在客户端无法使用。上面的类就是通过代码的方式将dll文件在客户端注册,生成tlb文件。
当然,这种方法写的东西比较多点,只是提供一种思路,为其他可能的项目准备。