我正在尝试从帐户中检索到期日期。

我试过了

DirectoryEntry user = new DirectoryEntry(iMem);

var AccountExpiration = DateTime.FromFileTime((int)user.Properties["accountExpires"].Value);

它不起作用,只给我错误“指定的类型转换无效”。

当我使用
var AccountExpiration = user.Properties["accountExpires"];

返回一个我无法读取的 com 对象。

使用 windows powershell,工作正常,我不明白为什么这行不通......

这是我在 powershell 中使用的代码
$Expires = [datetime]::FromFileTime($tmpUser.accountExpires)

最佳答案

您可以使用 System.DirectoryServices.AccountManagement 命名空间来完成此任务。从 UserPrincipal 获得 PrincipalContext 后,您可以检查 UserPrincipal.AccountExpirationDate 属性。

PrincipalContext context = new PrincipalContext(ContextType.Domain);

UserPrincipal p = UserPrincipal.FindByIdentity(context, "Domain\\User Name");

if (p.AccountExpirationDate.HasValue)
{
    DateTime expiration = p.AccountExpirationDate.Value.ToLocalTime();
}

如果您 do 想使用 DirectoryEntry ,请执行以下操作:
//assume 'user' is DirectoryEntry representing user to check
DateTime expires = DateTime.FromFileTime(GetInt64(user, "accountExpires"));

private Int64 GetInt64(DirectoryEntry entry, string attr)
{
    //we will use the marshaling behavior of the searcher
    DirectorySearcher ds = new DirectorySearcher(
    entry,
    String.Format("({0}=*)", attr),
    new string[] { attr },
    SearchScope.Base
    );

    SearchResult sr = ds.FindOne();

    if (sr != null)
    {
        if (sr.Properties.Contains(attr))
        {
            return (Int64)sr.Properties[attr][0];
        }
    }

    return -1;
}

解析 accountExpires 值的另一种方法是使用反射:
private static long ConvertLargeIntegerToLong(object largeInteger)
{
    Type type = largeInteger.GetType();

    int highPart = (int)type.InvokeMember("HighPart", BindingFlags.GetProperty, null, largeInteger, null);
    int lowPart = (int)type.InvokeMember("LowPart", BindingFlags.GetProperty | BindingFlags.Public, null, largeInteger, null);

    return (long)highPart <<32 | (uint)lowPart;
}

object accountExpires = DirectoryEntryHelper.GetAdObjectProperty(directoryEntry, "accountExpires");
var asLong = ConvertLargeIntegerToLong(accountExpires);

if (asLong == long.MaxValue || asLong <= 0 || DateTime.MaxValue.ToFileTime() <= asLong)
{
    return DateTime.MaxValue;
}
else
{
    return DateTime.FromFileTimeUtc(asLong);
}

10-05 20:07