VB.NET. Default login form not functioning

[Sport Girl]

Hi Everybody,

Please can somebody help me with this little task:

i created a login form in windows form from the default template in VB.NET but the problem is that it is not functioning even with the correct corresponding code.
I think the problem resides in event propreties but i am not sure, besides i don't have any idea about how to resolve this thing.

Can anybody give me an idea?
Thanks to all volunteers.
regards

[debasisdas]

Don't expect us to guess and solve your problem . Kindly post the code .

[Sport Girl]

I am using VB.NET 2008, SQL 2005

[CODE=vbnet]

Imports System.Windows. Forms

Imports System.Data.Sql Client
Imports System.Security
Imports System.Security .Cryptography

Public Class LoginForm
Inherits System.Windows. Forms.Form

' TODO: Insert code to perform custom authentication using the provided username and password
' (See http://go.microsoft.co m/fwlink/?LinkId=35339).
' The custom principal can then be attached to the current thread's principal as follows:
' My.User.Current Principal = CustomPrincipal
' where CustomPrincipal is the IPrincipal implementation used to perform authentication.
' Subsequently, My.User will return identity information encapsulated in the CustomPrincipal object
' such as the username, display name, etc.

Private Sub LoginForm_Load( ByVal sender As System.Object, ByVal e As System.EventArg s) Handles MyBase.Load

InitializeCompo nent()


End Sub
Private Sub OK_Click(ByVal sender As System.Object, ByVal e As System.EventArg s) Handles OK.Click

Dim AuthenticationR eader As System.Data.Sql Client.SqlDataR eader

'Intitalizes connection object
Dim SqlConnection As New SqlClient.SqlCo nnection
SqlConnection.C onnectionString = "Server=owner;d atabase=***"

'Initializes command object to execute statements.
Dim AuthenticationC ommand As New SqlClient.SqlCo mmand
AuthenticationC ommand.Connecti on = SqlConnection

'Declarations
Dim DBusername As String
Dim DBuserpassword
Dim DBuserID As Integer
Dim DBlogggedname As String
Dim DBprivilege As String

If UsernameTextBox .Text.Length = 0 Then


MessageBox.Show ("You must enter a username", "Invalid Username", MessageBoxButto ns.OK, MessageBoxIcon. Exclamation)
UsernameTextBox .Focus()



ElseIf PasswordTextBox .Text.Length = 0 Then

MessageBox.Show ("You must enter a password", "Invalid Password", MessageBoxButto ns.OK, MessageBoxIcon. Exclamation)
PasswordTextBox .Focus()
Else

DBusername = Me.UsernameText Box.Text
DBuserpassword = Me.PasswordText Box.Text


'Executes command
Dim AuthenticationS tring As String
AuthenticationS tring = "select * from *** where UserName= '" & UsernameTextBox .Text & "'"

AuthenticationC ommand.CommandT ext = AuthenticationS tring
SqlConnection.O pen()
AuthenticationC ommand.ExecuteN onQuery()

'Encrypt Password
Dim md5hasher As New MD5CryptoServic eProvider
Dim hashedBytes As Byte()
Dim encoder As New System.Text.UTF 8Encoding

hashedBytes = md5hasher.Compu teHash(encoder. GetBytes(Passwo rdTextBox.Text) )




AuthenticationR eader = AuthenticationC ommand.ExecuteR eader()
If AuthenticationR eader.HasRows Then
While (Authentication Reader.Read())
DBusername = AuthenticationR eader("UserName ")
DBuserpassword = AuthenticationR eader("Password ")
DBuserID = AuthenticationR eader("UserID")
DBlogggedname = AuthenticationR eader("Name")
DBprivilege = Trim(Authentica tionReader("Pri vilege"))
End While
Else

MessageBox.Show ("Invalid username!", "Error", MessageBoxButto ns.OK, MessageBoxIcon. Exclamation)
UsernameTextBox .Focus()
Exit Sub
End If
AuthenticationR eader.Close()

SqlConnection.C lose()



If bHashEquals(has hedBytes, DBuserpassword) Then


Dim Frame As New Frame()
Frame.Show()
Me.Hide()

Else

MessageBox.Show ("Invalid password!", "Error", MessageBoxButto ns.OK, MessageBoxIcon. Exclamation)
PasswordTextBox .Focus()
End If
End If




End Sub
Private Function bHashEquals(ByV al byHash1 As Byte(), ByVal byHash2() As Byte) As Boolean
bHashEquals = False
If byHash1.Length = byHash2.Length Then
Dim i As Integer
Do While (i < byHash1.Length) AndAlso (byHash1(i) = byHash2(i))
i = i + 1
Loop
If i = byHash1.Length Then
bHashEquals = True
End If
End If

End Function

Private Sub Cancel_Click(By Val sender As System.Object, ByVal e As System.EventArg s) Handles Cancel.Click
Me.Close()
End Sub

End Class

[/CODE]

Regards

[debasisdas]

are you getting any error in the code ?

run with break points and check the flow of control.

[Sport Girl]

the code does not have any errors with the debuggers

[Frinavale]

the code does not have any errors with the debuggers

Have you tried stepping through the code to see where it fails?
Glancing at this, everything seems to look fine....

-Frinny

[Sport Girl]

Well it is always prompting the messagebox "you must enter a username" whenever the situation is, besides the canccel button does not work in closing the form

[Plater]

Well I see this:
[code=vbnet]
If UsernameTextBox .Text.Length = 0 Then
MessageBox.Show ("You must enter a username", "Invalid Username", MessageBoxButto ns.OK, MessageBoxIcon. Exclamation)
UsernameTextBox .Focus()
'etc
[/code]
So that message should only be appearing if the UsernameTextBox is empty.

[Sport Girl]

Well yes but I get this message box even if i had a value for the username and/or a value for the password, besides the buttons are not functionning. the cancel button functions only when i press ESC button from the keybord.

I think there is a proprety in validation or something like this but i really don't know what is the problem exactly.

Regards

[Sport Girl]

Well yes but I get this message box even if i had a value for the username and/or a value for the password, besides the buttons are not functionning. the cancel button functions only when i press ESC button from the keybord.

I think there is a proprety in validation or something like this but i really don't know what is the problem exactly.

Regards

[Plater]

Set breakpoints in your program and step through it. I think you will find that UsernameTextbox will be empty.
Perhaps you mis-named your textboxes? Like mixed up which one is which?