My Program become messy

Question

Hey, can you guys help me out
My problem is that I'm making an app right now on visual basic
But after I run the program the app make no sense
It supposed to start with Login form but it's not it's start with debit transaction (that not supposed to be like that). After I close the debit transaction it doesn't go anywhere, instead it got out of the app entirely. How can I fix this?? I really hope you guys can answer me as soon as possible...
(Sorry for my Bad English)

Answer 1

To provide assistance with your current code, consider sharing the code via a GitHub repository and if so make sure you do not include sensitive information.

I have a Microsoft TechNet article which discusses performing login with and without a database with a GitHub repository which can be cloned to try out the examples.

In all the code samples the login form is set in project properties, the login form is hidden given proper credentials to show the main form which closes the app via Application.ExitThread().

Code for no database login form

Public Class LoginForm
    Private userID As String = "spicyramen06"
    Private password As String = "96619"
    Public Shared attempts As Integer = 0
    Private Sub LoginButton_Click(sender As Object, e As EventArgs) Handles LoginButton.Click

        attempts += 1

        If attempts >= 4 Then
            LoginButton.Enabled = False
            MessageBox.Show("Attempts exceeded")
            Exit Sub
        End If
        If Not String.IsNullOrWhiteSpace(UserNameTextBox.Text) AndAlso Not String.IsNullOrWhiteSpace(PasswordTextBox.Text) Then
            If UserNameTextBox.Text = userID AndAlso PasswordTextBox.Text = password Then
                My.Application.UserName = UserNameTextBox.Text
                Dim f As New MainForm
                Me.Hide()
                f.ShowDialog()
            Else
                Controls.OfType(Of TextBox).ToList().ForEach(Sub(tb) tb.Text = "")
                MessageBox.Show("Invalid logn")
            End If
        End If
    End Sub

    Private Sub CancelButton_Click(sender As Object, e As EventArgs) Handles CancelButton.Click
        Close()
    End Sub
End Class

Main form

Imports System.ComponentModel

Public Class MainForm
    Private Sub MainForm_Closing(sender As Object, e As CancelEventArgs) Handles Me.Closing
        Application.ExitThread()
    End Sub

    Private Sub MainForm_Shown(sender As Object, e As EventArgs) Handles Me.Shown
        Text = $"Welcome [{My.Application.UserName}]"
    End Sub
End Class

With a database dependent on requirements and if a database is used it can be more complex as explained in the TechNet article.

Answer 2

If you're building a Windows Forms app then note that when the main window closes the app terminates. The main window is the first form that is opened. It sounds like you initially created the transaction window and then added the login form. But the app sees the main window as the first form you had (transaction). Go to your app's startup code (or search for where your transaction window class is used). Somewhere is a call to create and display that form and it is probably being passed to Application.Run. Change it to create an instance of your login form instead.

To prevent the app from closing when the login form goes away (the startup window) you'll need to adjust the behavior. VB actually has better support for this through its custom application class. Set the ShutdownStyle to only close after all forms are closed. If you're not using that base class for some reason then you can implement the equivalent logic as discussed here.