添加一个引用，并用语句 System.Management ，则：

Add a reference and using statements for System.Management, then:

public static string GetOSFriendlyName()
{
    string result = string.Empty;
    ManagementObjectSearcher searcher = new ManagementObjectSearcher("SELECT Caption FROM Win32_OperatingSystem");
    foreach (ManagementObject os in searcher.Get())
    {
        result = os["Caption"].ToString();
        break;
    }
    return result;
}