WORKING WITH ACTIVE DIRECTORY LASTLOGONTIMESTAMP ATTRIBUTE

WORKING WITH ACTIVE DIRECTORY LASTLOGONTIMESTAMP ATTRIBUTE:



Active Directory includes an attribute – lastLogon – that tells you the last time a user or computer logged on.
The lastLogon attribute is not replicated from one domain controller to another.
There’s a brand-new attribute in the schema: lastLogonTimestamp.
This attribute also keeps track of the last time a user logged on to the domain, but this new attribute is replicated from one domain controller to another.
The lastLogonTimestamp is replicated only once every 14 days. This helps limit replication traffic.
The lastLogonTimestamp is stored as a 64-bit integer. When you query the lastLogonTimestamp you don’t get back a date-time like May 15, 2005 8:05 AM. Instead, you get back the number of 100-nanosecond intervals that passed between January 1, 1601 and the time the user last logged on.

Incidentally,VBScript can’t actually handle the 64-bit integer returned by lastLogonTimestamp.
But at least there is a workaround for this: ADSI’s IADsLargeInterger interface can break this into a pair of 32-bit integers for us.

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This code will bind to the user account in Active Directory and then use the Get method to retrieve the lastLogonTimestamp, storing that value in an IADsLargeInteger object with the object reference objLastLogon.

Set objUser = GetObject("LDAP://cn=Ken Myer, ou=Finance, dc=fabrikam, dc=com")
Set objLastLogon = objUser.Get("lastLogonTimestamp")

'The IADsLargeInteger object has two properties: HighPart, which stores the upper 32 bits of our 64-bit integer;
'and LowPart, which stores the lower 32 bits of the integer.

intLastLogonTime = objLastLogon.HighPart * (2^32) + objLastLogon.LowPart

'There are 1,000,000,000 nanoseconds in a second, 60 seconds in a minute and 1,440 minutes in every 24-hour day.
'This line of code tells us how many days have elapsed.

intLastLogonTime = intLastLogonTime / (60 * 10000000)
intLastLogonTime = intLastLogonTime / 1440

'Add the number of days that passed to the date January 1, 1601.

Wscript.Echo "Last logon time: " & intLastLogonTime + #1/1/1601#

Output:
Last logon time: 4/25/2005 2:54:09 PM

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Alternate solution:

'Use a method on DateTime called FromFileTime(long nanotime).This method returns a DateTime using
'the current Time Zone, so we don’t have to convert it.

Dim lastLogonDateTime As DateTime

Set objUser = GetObject("LDAP://cn=Ken Myer, ou=Finance, dc=fabrikam, dc=com")
Set objLastLogon = objUser.Get("lastLogonTimestamp")

lastLogonDateTime = DateTime.FromFileTime(objLastLogon)

Wscript.Echo "Last logon time: " & lastLogonDateTime.ToString

Working with null values in the .NET Framework

A null value is a value that doesn't refer to any object. It's the default value of reference-type variables(e.g., class, interface, delegate, string).



For example:

string sTest = "Test";
if (sTest == null) {
Console.WriteLine("sTest is Null")
}

This code works without any problems with C#,but there's no VB.NET equivalent of the null keyword. Instead,VB.NET uses the Nothing keyword. The following code demonstrates its use:

Dim sTest As String
If (sTest Is Nothing) Then
Console.WriteLine("sTest is Null")
End If

EXECUTE SQL COMMAND in Visual Basic

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Needed Import Statment:

Imports System.Data.SqlClient
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CASE 1: COMMAND which WILL NOT RETUN ANY ROW. Example: UPDATE


Dim connectionString as String
Dim connection as SqlConnection
Dim commandString as String
Dim command as SqlCommand

connectionString = "Data Source=CPHWIN0151;Initial Dialog=ABC Billing Infor;uid=abc_billing;pwd=abc@123"
commandString = "UPDATE ABCTable set costcenter=12345"

connection = New SqlConnection(connectionString)

Try
    connection.open()
    command = New SqlCommand(commandString,connection)
    command.ExecuteNonQuery()
    command.connection.close()
Catch ex As SQLException   

Finnaly
connection.close()

End Try

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CASE 2: COMMAND WHICH WILL RETURN ROW. Example: SELECT


Dim connectionString as String
Dim connection as SqlConnection
Dim commandString as String
Dim command as SqlCommand


connectionString = "Data Source=CPHWIN0151;Initial Dialog=ABC Billing Infor;uid=abc_billing;pwd=abc@123"
commandString = "SELECT objIdentifier,UID FROM V_MA_ORDER WHERE UID='12345'"

connection = New SqlConnection(connectionString)

Try
    connection.open()   
    command = New SqlCommand(commandString,connection)
   
    Dim dr As SqlDataReader = command.ExecuteReader

    Do While dr.Read()
        objId = dr(0).ToString.Trim
        uid = dr(1).ToString.trim
    Loop
   
    dr.close()
    command.connection.close()
Catch ex As SqlException

Finnaly
connection.close()

End Try

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