Tag: example

Identify all user keys in HKEY_USERS

January 5, 2018 /

This example shows how to enumerate the user keys in HKEY_USERS

Public Sub OutputRegKey(Key As RegistryKey)
Imports Microsoft.Win32

Public Class Form1
  Public arrUsers(100) As String, arrUsersMax As Integer = 0

  Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
    Dim i As Integer
    Dim txt As String = ""

    '-------------------------------------------------------------------
    ' identify the HKEY_Users
    '-------------------------------------------------------------------
    arrUsers(0) = ".DEFAULT"

    Dim regkey As RegistryKey = Registry.Users.OpenSubKey("")
    EnumerateHkeyUsers(regkey)
    regkey.Close()

    For i = 0 To arrUsersMax
      txt += arrUsers(i) & vbCrLf
    Next

    MsgBox(txt)
    End
  End Sub

  Sub EnumerateHkeyUsers(ByVal rkey As RegistryKey)
    Dim names As String() = rkey.GetSubKeyNames()
    Dim txt As String = ""

    For Each subkey In names
      txt = subkey.ToString

      If Len(txt) > 10 And InStr(LCase(txt), "_classes") = 0 Then
        arrUsersMax = arrUsersMax + 1
        arrUsers(arrUsersMax) = txt
      End If
    Next
  End Sub

End Class

SQL Left Function

September 27, 2017 /

The LEFT function allows you to extract a substring from a string, starting from the left-most character.

LEFT( string, number_of_characters )

Example:

SELECT LEFT('TechOnTheNet.com', 4);
Result: 'Tech'

SQL Delete Duplicate Records

September 19, 2017 /

This example shows how to remove duplicate uid records from a table named AD_Users

WITH CTE AS
(
SELECT ROW_NUMBER() OVER (PARTITION BY uid ORDER BY uid) AS Row, * FROM AD_Users
)
DELETE FROM CTE
WHERE ROW <> 1

Read Values From ListBox and Reference a 2-Dimensional Array

July 20, 2017 /

This example shows how to read entries from a ListBox and reference an array which contains numeric values corresponding to the selection.  This is useful if you want to do logic AND statements with the selection from the ListBox.

I used this method to assign numeric tags to the ListBox items.  This allowed me to assign a unique value to each combination of selections made.

Public Class Form1
 Dim arrTag(2, 5) As String, arrTagMax As Integer

Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
 LoadArray()
 End Sub

Private Sub ListBox1_SelectedIndexChanged(sender As System.Object, e As System.EventArgs) Handles lstACLGroups.SelectedIndexChanged
 Dim txt As String = ""
 Dim acc As Integer = 0

For i = 0 To lstACLGroups.SelectedItems.Count - 1
 txt += lstACLGroups.SelectedItems(i).ToString & vbCrLf

For j = 1 To 5
 If lstACLGroups.SelectedItems(i).ToString = arrTag(2, j) Then
 acc = acc + CInt(arrTag(1, j))
 End If
 Next
 Next

 TextBox1.Text = txt
 TextBox2.Text = acc.ToString
 End Sub

Sub LoadArray()
 Dim i As Integer

arrTag(1, 1) = 1
arrTag(2, 1) = "1 apple"

arrTag(1, 2) = 2
arrTag(2, 2) = "2 banana"

arrTag(1, 3) = 4
arrTag(2, 3) = "4 coconut"

arrTag(1, 4) = 8
arrTag(2, 4) = "8 dog"

arrTag(1, 5) = 16
arrTag(2, 5) = "16 elephant"

lstACLGroups.Items.Clear()
 For i = 1 To 5
   lstACLGroups.Items.Add(arrTag(2, i))
 Next

End Sub
End Class

Determine if a user belongs to a particular AD Group

June 13, 2017 /

This is the easiest way to determine if a user belongs to particular Active Directory user group using VB.NET without having to enumerate through all the user’s groups.

Public Function IsInGroup(ByVal GroupName As String) As Boolean
 Dim MyIdentity As System.Security.Principal.WindowsIdentity = System.Security.Principal.WindowsIdentity.GetCurrent()
 Dim MyPrincipal As System.Security.Principal.WindowsPrincipal = New System.Security.Principal.WindowsPrincipal(MyIdentity)
 Return MyPrincipal.IsInRole(GroupName)
End Function