startp up object

  • Thread starter Thread starter hkadhim
  • Start date Start date
H

hkadhim

hi all,
i am using the following:
Public Sub Main()

Try

'set the ado connection string

Dim strConnection As String = "Provider=" & "Microsoft.Jet.OLEDB.4.0;" &
"Data Source=C:\MyFolder\data1.mdb;" & "Jet OLEDB:Database Password=" & ""

'try to open the ado connection

cnn.Open(strConnection)

'set cursor location of recordset to client...

'rsControl.CursorLocation = ADODB.CursorLocationEnum.adUseClient

MyfrmLogin.Show()

Catch ex As Exception

MessageBox.Show(ex.ToString())

Finally

End Try

End Sub

I am trying to set the database connection from the Sub Main(). now when i
go to project properties, i selected Sub Main as the startup object but it
will show for a while and unload itself quickly. i used to do it in VB6 all
the time but i am now with VB.NET 2003 i am a bit confused. how can i force
the project to start from the Sub Main()?

thanks alot
 
It sounds like (or reads like) you are new to .NET. I believe that your Sub
Main is being called but your form isn't.

All the code that you wrote below looks like typical VB 6 code, but VB.NET
isn't just VB 7.0, it's a complete re-write of the architecture and
therefore the language as well.

You're using classic ADO, trying to set a client-side cursor when you could
be using ADO.NET that natively works with disconnected data.

You're calling the show method of your form, but where is it's
instantiation?
 
thanks Scott for your reply,
you are right, i am new to the .NET world and its a bit confusing!
this is the entire class:
Imports ADODB

Imports System.Data.OleDb

Imports System.Data.SqlClient

Module OpenDBConnection

Public MyfrmLogin As New frmLogin

Dim MyfrmMain As New frmMain

Dim cnn As New ADODB.Connection

Dim rsControl As New ADODB.Recordset

Dim strSQL As String 'this is the source

Dim strPath As String = Application.StartupPath()

Public Sub Main()

Try

'set the ado connection string

Dim strConnection As String = "Provider=" & "Microsoft.Jet.OLEDB.4.0;" &
"Data Source=C:\MyFolder\Data1.mdb;" & "Jet OLEDB:Database Password=" & ""

'try to open the ado connection

cnn.Open(strConnection)

'set cursor location of recordset to client...

'rsControl.CursorLocation = ADODB.CursorLocationEnum.adUseClient

MyfrmLogin.Show()

Application.Run() 'added this line and was able to keep the apllication
running

Catch ex As Exception

MessageBox.Show(ex.ToString())

Finally

End Try

End Sub

Public Sub LogonProcess()

Dim UserLogin, UserPass As String

UserLogin = MyfrmLogin.txtUserName.Text.Trim()

UserPass = MyfrmLogin.txtPassword.Text.Trim()

Try

rsControl.CursorLocation = ADODB.CursorLocationEnum.adUseClient

strSQL = "SELECT * FROM Employees WHERE Username = '" & UserLogin & "' AND
Password = '" & UserPass & "'"

rsControl.Open(strSQL, cnn, CursorTypeEnum.adOpenStatic,
LockTypeEnum.adLockReadOnly, CommandTypeEnum.adCmdText) 'compiler gives
me an error in this line

With rsControl

If Not .EOF And Not .BOF Then

MyfrmMain.Show()

MyfrmLogin.Hide()

Else

MsgBox("Your login details are INCORRECT.")

End If

End With

Catch ex As Exception

MessageBox.Show(ex.ToString())

Finally

End Try

End Sub

End Module

I added Application.Run() and was able to keep the application running. but
now when i try to open the recordset the program terminates and i get an
exception error. do you see anything wrong in this line:

rsControl.Open(strSQL, cnn, CursorTypeEnum.adOpenStatic,
LockTypeEnum.adLockReadOnly, CommandTypeEnum.adCmdText) 'compiler gives
me an error in this line

thanks a lot
 
See Chris's reply below to start your form. What I still don't get though
is why you are using ADO at all. You are importing the new ADO.NET
namespaces (and you get references to these assemblies automatically anyway)
so why not just use ADO.NET for better performance and say goodbye to
classic ADO.
 
thanks Chris for your reply,
do you think if i create a dummy startUp form and make it as the startup
object instead of looping (using application.Run() ) will be better?

thanks alot
 
Application.Run() isn't a loop.

This is the preferred way unless you want to set your form as the startup
object and write your connection stuff in the form's load event.

hkadhim said:
thanks Chris for your reply,
do you think if i create a dummy startUp form and make it as the startup
object instead of looping (using application.Run() ) will be better?

thanks alot
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