查詢WMI類Win32_QuickFixEngineering返回mucho怪異時間戳（C＃）

Question

類文檔here。 InstalledOn屬性在安裝修復程序時應該有一個（well，duh）的時間戳。但文檔沒有說明格式。我得到一些無法理解的東西，但它顯然意味着什麼。 「01ca56402c180b70」十六進制數非常明顯，但是是什麼？

另一件事：爲什麼前幾個項目看起來像GUID？他們的意思是什麼？

DA代碼：

ManagementScope scope; 
ConnectionOptions options = new ConnectionOptions(); 
options.Username = tbUsername.Text; 
options.Password = tbPassword.Password; 
options.Authority = String.Format("ntlmdomain:{0}", tbDomain.Text); 
scope = new ManagementScope(String.Format("\\\\{0}\\root\\cimv2", tbHost.Text), options); 
scope.Connect(); 
ManagementObjectSearcher searcher = new ManagementObjectSearcher(scope, new ObjectQuery("SELECT * FROM Win32_QuickFixEngineering")); 
foreach (ManagementObject queryObj in searcher.Get()) 
{ 
    wmiResults.Text += String.Format("{0} <{1}>: {2} (Installed {3} by '{4}')", 
            queryObj["HotFixID"], 
            queryObj["Caption"], 
            queryObj["Description"], 
            queryObj["InstalledOn"], 
            queryObj["InstalledBy"] 
            ); 
} 

DA輸出：

{87796B93-94D0-A0C7-EFC4-FF34426626BC} <>: (Installed 20090513 by '') 
{D93F9C7C-AB57-44C8-BAD6-1494674BCAF7} <>: (Installed 20090928 by '') 
{9AD2FB23-AC50-435C-8ABC-8119D29CF0C1} <>: (Installed 20090929 by '') 
{62D3B51B-F56D-40F0-8C32-EAB204ADF752} <>: (Installed 20090513 by '') 
{EC038F86-AC1E-4C30-AEFB-B6B8A3922DCD} <>: (Installed 20091116 by '') 
{D1219E04-62FF-49D0-804C-A27F968E50A5} <>: (Installed 20091116 by '') 
{1DE62EBA-6684-2483-3409-CEBADBF8A31E} <>: (Installed 20090513 by '') 
{8CA89076-2A6D-42C3-AA24-F203C9E5DBF3} <>: (Installed 20090513 by '') 
{F5E29D9D-519A-36C7-87E3-9A22A8180B1B} <>: (Installed 20091016 by '') 
KB948609 <http://support.microsoft.com/?kbid=948609>: Update (Installed 01c9d3cb9b46a87c by 'S-1-5-21-2756995651-916083937-3196967445-500') 
KB948610 <http://support.microsoft.com/?kbid=948610>: Update (Installed 01c9d3cb9b4909dd by 'S-1-5-21-2756995651-916083937-3196967445-500') 
KB951978 <http://support.microsoft.com/?kbid=951978>: Update (Installed 01ca408d02d6cdbe by 'S-1-5-18') 
KB952287 <http://support.microsoft.com/?kbid=952287>: Hotfix (Installed 01ca408d02d925c8 by 'S-1-5-18') 
KB954155 <http://support.microsoft.com/?kbid=954155>: Security Update (Installed 01ca56402c10e74d by 'S-1-5-18') 
KB955020 <http://support.microsoft.com/?kbid=955020>: Update (Installed 01ca408d02d925c8 by 'S-1-5-18') 
KB955302 <http://support.microsoft.com/?kbid=955302>: Update (Installed 01ca408d02db7dd2 by 'S-1-5-18') 
KB956250 <http://support.microsoft.com>: Update (Installed 01ca66e5e6fc6b70 by 'S-1-5-21-501351562-481299158-1019697294-11592') 
KB958481 <http://support.microsoft.com/?kbid=958481>: Update (Installed 01ca408d02db7dd2 by 'S-1-5-18') 
KB958483 <http://support.microsoft.com/?kbid=958483>: Update (Installed 01ca408d02ddd5dc by 'S-1-5-18') 
KB958644 <http://support.microsoft.com/?kbid=958644>: Security Update (Installed 01ca57f748bfe059 by 'S-1-5-21-2756995651-916083937-3196967445-500') 
KB958869 <http://support.microsoft.com/?kbid=958869>: Security Update (Installed 01ca56402c10e74d by 'S-1-5-18') 
KB959772 <http://support.microsoft.com/?kbid=959772>: Update (Installed 01ca408d02ddd5dc by 'S-1-5-18') 
KB968389 <http://support.microsoft.com/?kbid=968389>: Update (Installed 01ca408d02e02de6 by 'S-1-5-18') 
KB968816 <http://support.microsoft.com/?kbid=968816>: Security Update (Installed 01ca45c1ebfd041f by 'S-1-5-18') 
KB971486 <http://support.microsoft.com/?kbid=971486>: Security Update (Installed 01ca56402c1348ae by 'S-1-5-18') 
KB972594 <http://support.microsoft.com/?kbid=972594>: Security Update (Installed 01ca408d02e02de6 by 'S-1-5-18') 
KB973525 <http://support.microsoft.com/?kbid=973525>: Security Update (Installed 01ca56402c1348ae by 'S-1-5-18') 
KB974455 <http://support.microsoft.com/?kbid=974455>: Security Update (Installed 01ca56402c15aa0f by 'S-1-5-18') 
KB974571 <http://support.microsoft.com/?kbid=974571>: Security Update (Installed 01ca56402c15aa0f by 'S-1-5-18') 
KB975467 <http://support.microsoft.com/?kbid=975467>: Security Update (Installed 01ca56402c15aa0f by 'S-1-5-18') 
KB975517 <http://support.microsoft.com/?kbid=975517>: Security Update (Installed 01ca56402c180b70 by 'S-1-5-18') 

Answer 1

http://blogs.msdn.com/oldnewthing/archive/2003/09/05/54806.aspx給出解釋不同類型的時間戳的信息。它看起來像你有一個Win32 FILETIME。

Answer 2

安裝< NTP時間戳>通過 '<安全標識符>'

在字符串的開頭是NTP時間戳。你不能很容易地把它們變成System.DateTime。

String s = "01c9d3cb9b46a87c"; 
DateTime dt = DateTime.FromFileTime(Int64.Parse(s, System.Globalization.NumberStyles.HexNumber)); 

有關NTP時間戳的更多信息，請閱讀RFC（不用擔心，它實際上是一個「短」 RFC）爲：http://www.faqs.org/rfcs/rfc958.html

在字符串的結尾是安全標識符佔Local System是'S-1-5-18'。

有關安全標識符的詳細信息，請參閱：http://technet.microsoft.com/en-us/library/cc780850%28WS.10%29.aspx