.NET Framework CLR 版本检测

我写了一个 c# 程序来检测 .net framework clr 版本。

在 ubuntu 操作中的运行结果：

ben@ben-m4000t:~/work$ ./clrinfo.exe
      os version: unix 2.6.31.16
     clr version: 2.0.50727.1433  ( mono 2.4.2.3 )
default encoding: system.text.utf8encoding

available frameworks:
  mono 1.0 profile
  mono 2.0 profile

在 windows vista 操作系统中的运行结果：

e:csclrinfo> clrinfo.exe
      os version: microsoft windows nt 6.0.6002 service pack 2
     clr version: 2.0.50727.4200  ( net 2.0.50727.4200 )
default encoding: system.text.dbcscodepageencoding

available frameworks:
  net 2.0.50727

注意，这个程序检测的是 .net framework clr 版本，而不是 .net framework 版本。实际上这个 windows vista 操作系统中安装了 .net framework 的以下版本：

• 2.0.50727.4016
• 3.0.30729.4037
• 3.5.30729.01

  而三个版本的 .net framework 的 clr 版本都是 2.0.50727。

  在 windows server 2003 操作系统中的运行结果：

  e:csclrinfo> clrinfo.exe
        os version: microsoft windows nt 5.2.3790 service pack 2
       clr version: 2.0.50727.3603  ( net 2.0.50727.3603 )
  default encoding: system.text.dbcscodepageencoding
  
  available frameworks:
    net 1.1.4322
    net 2.0.50727
    net 4.0.21006
  

  另外，microsoft windows sdk 中的 clrver.exe 的运行结果：

  e:csclrinfo> clrver.exe
  versions installed on the machine:
  v1.1.4322
  v2.0.50727
  v4.0.21006
  

  我们来看看源程序吧。下面是 clrinfo.cs：

  using system;
  using system.text;
  
  namespace skyiv
  {
    public class clrinfo
    {
      static void main()
      {
        console.writeline(      os version: {0}, environment.osversion);
        console.writeline(     clr version: {0}  ( {1} ), environment.version, runtimeframework.currentframework);
        console.writeline(default encoding: {0}, encoding.default);
        console.writeline();
        console.writeline(available frameworks:);
        foreach (var frame in runtimeframework.availableframeworks) console.writeline(   + frame);
      }
    }
  }
  

  下面是 runtimeframework.cs (该程序是从 nunit 的源程序中的同名文件改写而来的)：

  using system;
  using system.reflection;
  using system.collections.generic;
  using microsoft.win32;
  
  namespace skyiv
  {
    public enum runtimetype
    {
      any,   // any supported runtime framework
      net,   // microsoft .net framework
      netcf, // microsoft .net compact framework
      sscli, // microsoft shared source cli
      mono,  // mono
    }
  
    // see https://nunit.org, this class from nunit project's runtimeframework.cs
    // runtimeframework represents a particular version of a common language runtime implementation.
    [serializable]
    public sealed class runtimeframework
    {
      public runtimetype runtime { get; private set; }
      public version version { get; private set; }
      public string displayname { get; private set; }
      static runtimeframework currentframework;
  
      public static runtimeframework currentframework
      {
        get
        {
          if (currentframework == null)
          {
            var monoruntimetype = type.gettype(mono.runtime, false);
            var runtime = monoruntimetype != null ? runtimetype.mono : runtimetype.net;
            currentframework = new runtimeframework(runtime, environment.version);
            if (monoruntimetype != null)
            {
              var method = monoruntimetype.getmethod(getdisplayname, bindingflags.static |
                bindingflags.nonpublic | bindingflags.declaredonly | bindingflags.exactbinding);
              if (method != null) currentframework.displayname = (string)method.invoke(null, new object[0]);
            }
          }
          return currentframework;
        }
      }
  
      public static runtimeframework[] availableframeworks
      {
        get
        {
          var frameworks = new list();
          foreach (var framework in getavailableframeworks(runtimetype.net)) frameworks.add(framework);
          foreach (var framework in getavailableframeworks(runtimetype.mono)) frameworks.add(framework);
          return frameworks.toarray();
        }
      }
  
      public static bool ismonoinstalled()
      {
        if (currentframework.runtime == runtimetype.mono) return true;
        // don't know how to do this on linux yet, but it's not a problem since we are only supporting mono on linux
        if (environment.osversion.platform != platformid.win32nt) return false;
        var key = registry.localmachine.opensubkey(@softwarenovellmono);
        if (key == null) return false;
        var version = key.getvalue(defaultclr) as string;
        if (string.isnullorempty(version)) return false;
        return key.opensubkey(version) != null;
      }
  
      // returns an array of all available frameworks of a given type, for example, all mono or all .net frameworks.
      public static runtimeframework[] getavailableframeworks(runtimetype rt)
      {
        var frameworks = new list();
        if (rt == runtimetype.net && environment.osversion.platform != platformid.unix)
        {
          var key = registry.localmachine.opensubkey(@softwaremicrosoft.netframeworkpolicy);
          if (key != null)
            foreach (var name in key.getsubkeynames())
              if (name.startswith(v))
                foreach (var build in key.opensubkey(name).getvaluenames())
                  frameworks.add(new runtimeframework(rt, new version(name.substring(1) + . + build)));
        }
        else if (rt == runtimetype.mono && ismonoinstalled())
        {
          var framework = new runtimeframework(rt, new version(1, 1, 4322));
          framework.displayname = mono 1.0 profile;
          frameworks.add(framework);
          framework = new runtimeframework(rt, new version(2, 0, 50727));
          framework.displayname = mono 2.0 profile;
          frameworks.add(framework);
        }
        return frameworks.toarray();
      }
  
      public runtimeframework(runtimetype runtime, version version)
      {
        runtime = runtime;
        version = version;
        displayname = runtime.tostring() +   + version.tostring();
      }
  
      public override string tostring()
      {
        return displayname;
      }
    }
  }
  

  在 runtimeframework 类的 currentframework 属性中，如果发现当前环境是 mono 的话，就通过反射调用 mono.runtime 类的静态方法 getdisplayname 来设置 displayname 属性。

  在 runtimeframework 类的静态方法 getavailableframeworks 中，如果发现当前操作系统不是 unix 的话，就通过遍历注册表的 softwaremicrosoft.netframeworkpolicy 项来检测 .net framework clr 版本。

  下面是 makefile (关于 makefile，可以参见：gun make 中文手册)：

  csc = csc
  src1 = clrinfo.cs runtimeframework.cs
  
  clrinfo.exe: $(src1)
  	$(csc) -out:$@ $(src1)
  

  在 linux 操作系统下可以用 make 命令编译。在 windows 操作系统下可以用 nmake 命令编译。

  注意，mono 的 c# 编译器是 gmcs，但是她有个别名叫 csc ，如下所示：

  ben@ben-m4000t:~$ ls -l /usr/bin/csc /usr/bin/gmcs
  lrwxrwxrwx 1 root root  4 2009-11-01 18:53 /usr/bin/csc -> gmcs
  -rwxr-xr-x 1 root root 75 2009-09-23 23:04 /usr/bin/gmcs
  ben@ben-m4000t:~$ cat /usr/bin/gmcs
  #!/bin/sh
  exec /usr/bin/mono $mono_options /usr/lib/mono/2.0/gmcs.exe $@
  ben@ben-m4000t:~$ gmcs --version
  mono c# compiler version 2.4.2.3
  ben@ben-m4000t:~$ csc --version
  mono c# compiler version 2.4.2.3