如何使用C#读取“uSNChanged”属性

Question

我希望你能帮我使用C#通过uSNChanged的值在ActiveDirectory中获取最近修改或创建的属性...我还尝试找到uSNChanged的最大值，你能帮我找到解决方案吗？谢谢。

- Raja

Answer 1

通过.NET有两种方法检索uSNChanged属性：

1. Include a reference to a COM library: "Active DS Type Library", then you need to use the IADsLargeInterger to retrieve the value and finally convert it to a long. For example:

   IADsLargeInteger li_ad = (IADsLargeInteger)oUser.Properties["USNChanged"].Value;
   long l_uChanged = GetLongFromLargeInteger( li_ad );
   
   static long GetLongFromLargeInteger(  IADsLargeInteger  Li )
   {
       long retval = Li.HighPart;
       retval <<=32;
       retval |=(uint)Li.LowPart;
       return retval;
   }
   

2. Translate the values only using C#. Thanks to Simon Gilbee, we have this option:

    long usnChanged = ConvertADSLargeIntegerToInt64(oUser.Properties["USNChanged"].Value);
   
    public static Int64 ConvertADSLargeIntegerToInt64(object adsLargeInteger)
    {
      var highPart = (Int32)adsLargeInteger.GetType().InvokeMember("HighPart", System.Reflection.BindingFlags.GetProperty, null, adsLargeInteger, null);
      var lowPart  = (Int32)adsLargeInteger.GetType().InvokeMember("LowPart",  System.Reflection.BindingFlags.GetProperty, null, adsLargeInteger, null);
      return highPart * ((Int64)UInt32.MaxValue + 1) + lowPart;
    }
   

我强烈推荐您选择第二个选项，以避免与旧版ActiveDs库出现问题，并且不需要在这个列表上寻找答案。

- Brett Veenstra

Answer 2

我有解决方案了，大家可以通过这个属性HighestCommittedUsn获取域控制器的最大不变值。

- Rajakumar