Login Form - Not working - vb.net

Question

Struggling with creating a login from a text file database. The information needs to be manually entered into the text file before it works... see my code below for the form. Its not letting me login.
Public Class UserLogin
Private PWD As String
Public User As User
Public Users As List(Of User) = New List(Of User)
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
Me.Close()
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Try
If isValidData() Then
If isValidUser() Then
MessageBox.Show("Login Successful")
Form2.Show()
Me.Hide()
Else
MessageBox.Show("Incorrect Username or password")
End If
End If
Catch ex As Exception
MessageBox.Show(ex.Message & vbCrLf & vbCrLf & ex.GetType.ToString & vbCrLf & vbCrLf & ex.StackTrace, "User Does not Exist")
End Try
End Sub
Private Function isValidData() As Boolean
Return Validator.IsPresent(TextBox1, "Username") AndAlso
Validator.IsPresent(TextBox2, "Password")
End Function
Private Function isValidUser() As Boolean
Return UserDB.ValidateUser("Username", "Password")
End Function
Public Sub setPath(cwd As String)
PWD = cwd
End Sub
End Class
User class below :
Public Class User
Public Sub New()
End Sub
Public Sub New(Username As String, Password As String)
Me.Username = Username
Me.Password = Password
End Sub
Public Property Username As String
Public Property Password As String
Public Function GetDisplayText(sep As String) As String
Dim text As String = Username & sep & Password
Return text
End Function
End Class
UserDB class Below
Imports System.IO
Public Class UserDB
Private Const Databasename = "C:\Depreciate\Users.txt"
Public User As New User
Public Shared Users As List(Of User) = New List(Of User)
Public Shared Function GetUsers(Dir As String) As List(Of User)
Dim Users As New List(Of User)
Dim textIn As New StreamReader(
New FileStream(Databasename, FileMode.OpenOrCreate, FileAccess.Read))
Do While textIn.Peek <> -1
Dim row As String = textIn.ReadLine
Dim columns As String() = row.Split(CChar(","))
Dim User As New User
User.Username = columns(0)
User.Password = columns(1)
Users.Add(User)
Loop
textIn.Close()
Return Users
End Function
Public Shared Function ValidateUser(username As String, password As String) As Boolean
Dim Validated = False
For Each userEntry As User In Users
If username = userEntry.Username AndAlso password = userEntry.Password Then
Validated = True
Exit For
End If
Next
Return Validated
End Function
End Class

Answer 1

looks like you compare all user names and passwords to the strings "Username" and "Password" by calling:
Return UserDB.ValidateUser("Username", "Password")
in isValidUser.Probably you should better pass the actual username and the password which the user has typed instead?

Answer 2

There are a couple of problems in your code:
First I can't see anywhere the call to UserDB.GetUsers that should initialize the list of users from the file. But also assuming that you have made the call in some other place, there is another problem in that method.
This line inside the GetUsers method creates a new variable of type List(Of User) and name it with the same name of the Shared one effectively hiding the one declared at the global class level
Dim Users As New List(Of User)
Then your code continue and fills a variable named Users but this variable is not the shared one declared at the class global level. Of course, when you search your username and password in the shared variable you don't find anything.
Just remove that line and let the call To GetUsers fill the same variable used in the check
(Of course I also assume that when you call UserDB.ValidateUser you will pass an actual Username and a password and not the placeholders string that you are using in the code above)