active-directory - 如何将 System.DirectoryEntry "uSNChanged"属性值更改为 Int64

Question

我正在尝试获取目录服务对象的“uSNChanged”值的 Int64 值。不幸的是，它总是作为某种 COM 对象回来。我尝试使用转换为 Int64、调用 Int64.Parse() 和调用 Convert.ToInt64()。这些都不起作用。

对于给定的 DirectoryEntry 对象，此代码将显示属性:

    private static void DisplaySelectedProperties(DirectoryEntry objADObject)
    {
        try
        {
            string[] properties = new string[] {
                "displayName",
                "whenCreated",
                "whenChanged",
                "uSNCreated",
                "uSNChanged",
            };

            Console.WriteLine(String.Format("Displaying selected properties of {0}", objADObject.Path));
            foreach (string strAttrName in properties)
            {
                foreach (var objAttrValue in objADObject.Properties[strAttrName])
                {
                    string strAttrValue = objAttrValue.ToString();
                    Console.WriteLine(String.Format("   {0, -22} : {1}", strAttrName, strAttrValue));
                }
            }
            Console.WriteLine();
        }
        catch (Exception ex)
        {
            throw new ApplicationException(string.Format("Fatal error accessing: {0} - {1}", objADObject.Path, ex.Message), ex);
        }
    }

这是输出:

Displaying selected properties of LDAP://server/o=org/cn=obj   displayName            : Display Name   whenCreated            : 7/8/2009 7:29:02 PM   whenChanged            : 7/8/2009 10:42:23 PM   uSNCreated             : System.__ComObject   uSNChanged             : System.__ComObject

How do I convert that System.__ComObject into a Int64?

---

Solution Used:

This is the solution I used based on marc_s's solution below:

    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;
    }

Answer 1

我在我的 ADSI 浏览器中使用了这段代码 BeaverTail这是用 C# 编写的:

Int64 iLargeInt = 0;

IADsLargeInteger int64Val = (IADsLargeInteger)oPropValue.LargeInteger;
iLargeInt = int64Val.HighPart * 4294967296 + int64Val.LowPart;

据我所知，这应该可以正常工作。

马克