代码如下：

public static bool checkFrameWork(string destVersion){bool ver1 = GetVersionFromRegistry(destVersion);if (ver1)return true;else{return Get45PlusFromRegistry();}}//reference:https://docs.microsoft.com/en-us/dotnet/framework/migration-guide/how-to-determine-which-versions-are-installedpublic static bool Get45PlusFromRegistry(){const string subkey = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\";using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey(subkey)){if (ndpKey != null && ndpKey.GetValue("Release") != null){return CheckFor45PlusVersion((int)ndpKey.GetValue("Release"));}return false;}}// Checking the version using >= will enable forward compatibility.public static bool CheckFor45PlusVersion(int releaseKey){if (releaseKey >= 378389)return true;// This code should never execute. A non-null release key should mean// that 4.5 or later is installed.return false;}public static bool GetVersionFromRegistry(string destVersion){ArrayList versions = new ArrayList();// Opens the registry key for the .NET Framework entry.using (RegistryKey ndpKey =RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, "").OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\")){// As an alternative, if you know the computers you will query are running .NET Framework 4.5 // or later, you can use:// using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, // RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))foreach (string versionKeyName in ndpKey.GetSubKeyNames()){if (versionKeyName.StartsWith("v")){RegistryKey versionKey = ndpKey.OpenSubKey(versionKeyName);string name = (string)versionKey.GetValue("Version", "");string sp = versionKey.GetValue("SP", "").ToString();string install = versionKey.GetValue("Install", "").ToString();if (install == "") //no install info, must be later.{Console.WriteLine(name);versions.Add(name);}//Console.WriteLine(versionKeyName + "  " + name);else{if (sp != "" && install == "1"){//Console.WriteLine(versionKeyName + "  " + name + "  SP" + sp);Console.WriteLine(name);versions.Add(name);}}if (name != ""){continue;}foreach (string subKeyName in versionKey.GetSubKeyNames()){RegistryKey subKey = versionKey.OpenSubKey(subKeyName);name = (string)subKey.GetValue("Version", "");if (name != "")sp = subKey.GetValue("SP", "").ToString();install = subKey.GetValue("Install", "").ToString();if (install == "") //no install info, must be later.{//Console.WriteLine(versionKeyName + "  " + name);//Console.WriteLine(name);versions.Add(name);}else{if (sp != "" && install == "1"){//Console.WriteLine("  " + subKeyName + "  " + name + "  SP" + sp);//Console.Write(name);versions.Add(name);}else if (install == "1"){//Console.WriteLine("  " + subKeyName + "  " + name);//Console.WriteLine(name);versions.Add(name);}}}}}object[] verArr = versions.ToArray();foreach (object o in verArr){Version ver;string str = o.ToString();if (str == "")ver = new Version("1.0");elsever = new Version(str);if (ver >= new Version(destVersion))return true;}}return false;}
复制代码

其中还有一点小瑕疵，有兴趣的自己看一看修改一下就好了。

在使用的时候，我们只需要调用checkFrameWork函数就可以了。