Check which .NET Framework version is installed from command line

class CDotNetVersion
{
    public List<string> versionList { get; set; }
    public CDotNetVersion()
    {
        versionList = new List<string>();
    }
    public void GetVersion()
    {
        versionList = new List<string>();
        using (var ndpKey = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP"))
        {
            Action<RegistryKey, Action<RegistryKey, string>> processKids = (node, action) =>
            {
                foreach (var childname in node.GetSubKeyNames())
                    using (var child = node.OpenSubKey(childname))
                        action(child, childname);
            };
            Action<RegistryKey, Func<RegistryKey, bool>> visitDescendants = null;
            visitDescendants = (regkey, isDone) =>
            {
                if (!isDone(regkey))
                    processKids(regkey, (subkey, subkeyname) => visitDescendants(subkey, isDone));
            };
            processKids(ndpKey, (versionKey, versionKeyName) =>
            {
                if (Regex.IsMatch(versionKeyName, @"^v\d"))
                {
                    visitDescendants(versionKey, key =>
                    {
                        bool isInstallationNode = Equals(key.GetValue("Install"), 1) && key.GetValue("Version") != null;
                        if (isInstallationNode)
                            versionList.Add(
                                key.Name.Substring(ndpKey.Name.Length + 1)
                                + (key.GetValue("SP") != null ? ", service pack " + key.GetValue("SP") : "")
                                + " (" + key.GetValue("Version") + ") "
                            );
                        return isInstallationNode;
                    });
                }
            });
        }
    }
}

.Net Framework Version: v2.0.50727, service pack 2 (2.0.50727.5420) 
.Net Framework Version: v3.0, service pack 2 (3.0.30729.5420) 
.Net Framework Version: v3.5, service pack 1 (3.5.30729.5420) 
.Net Framework Version: v4\Client (4.5.50709) 
.Net Framework Version: v4\Full (4.5.50709) 
.Net Framework Version: v4.0\Client (4.0.0.0)