Visual Basic

set dllreg = "wscript.shell"
dllreg.run "regsvr32 /u C:\Program Files (x86)\histori.dll"

Form2

Public Event refreshdg1(ByVal st As String)

Private Sub

.......Some condition -->True then
....... Update database table

'I tried three ways here


1-    Raiseevent refreshdg1(s1)


2- 

        Dim StrCon As String
        Dim conn As SqlConnection
        StrCon = ConfigurationManager.AppSettings("StrCon")
        conn = New SqlConnection(StrCon)
        conn.Open()
       Dim ds As New SqlDataAdapter("Select * from Tag_History where Tag_ID = '" + s1 + "' ", conn)
      Dim commandBuilder As New SqlCommandBuilder(listadapter)

      Dim table As New DataTable()

      table.Locale = System.Globalization.CultureInfo.InvariantCulture
     listadapter.Fill(table)

     Form1.dg1.DataSource = table
     conn.Close()


3-   Form1.refreshdg(s1)


End sub



Form1:

Addhandler Form2.(I cant refreshdg1 here)


  Private Sub refreshdg(ByVal s As String)
        Dim f As New Parking_control
        AddHandler f.refreshdg1, AddressOf refreshdg
        Dim StrCon As String
        Dim conn As SqlConnection
        StrCon = ConfigurationManager.AppSettings("StrCon")
        conn = New SqlConnection(StrCon)
        conn.Open()
        
        Dim person As String
        person = s

        Dim ds1 As New SqlDataAdapter("Select * from Tag_History where Name = '" + person + "' ", conn)
        Dim commandBuilder As New SqlCommandBuilder(ds1)


        Dim table As New DataTable()

        table.Locale = System.Globalization.CultureInfo.InvariantCulture
        listadapter1.Fill(table)
        table.Columns(0).ColumnName = "Tag ID"
        table.Columns(1).ColumnName = "Date   Time"
        table.Columns(3).ColumnName = "Tag Status"
        dg1.DataSource = table
  
        conn.Close()

    End Sub