Form Show

[Acalderon]

Hello, good day.

I am developing a project in vb.net, I had wrote several in vb 6.0 and I remember that when you want to show a form, you just type:

form1.show
me.hide

Now in vb.Net, I am having trouble with this, firts I don´t know what the error is, it only turns to underlined text, then, I delete the show part to see the properties menu that appears when you put a point, but it doesn´t show the Show() option.

I also read that I can put my log in form as a dialog form, and put the form with the links to the other ones as the Main, but I dont know how to change my forms to do this.

Can anyone help me with this?

[Phil Weber]

In VB.NET, a form is a class; you must create an instance of the class (using the "New" keyword) before you may use it. Try this:

Dim frm As New Form1
frm.Show()

[Acalderon]

Hi, good day.

I did that and when the event is fired the form sends an error:

An unhandled exception of type 'System.NullReferenceException' occurred in system.windows.forms.dll

I dont know what to do !!!!

[Phil Weber]

A null reference exception usually means that you're trying to use an object that you've forgotten to initialize ("New"). Please post the code that's causing the error (no more than a dozen or so lines).

[Acalderon]

Thanks Phil, It was the "new" word that was missing.

Now I read that I can "start" my solution in a Main form, and use the login form as a dialog, so I am on this now, but I have two text boxes with user and password and a validation boolean function, so, I have to send back to the main sub that the user has been validated, i have a couple of buttons also to "validate" the user.

How do I do this, I mean which control has to be "true" and return the value to the Main sub?

Thanks and best regards.

[Phil Weber]

I would probably add a read-only property to the form to indicate whether the user successfully logged in:

Private Success As Boolean

Public ReadOnly Property IsLoggedIn() As Boolean
    Get
        Return Success
    End Get
End Property

Set the Success variable equal to the result of your validation function. In your main form, check the value of LoginForm.IsLoggedIn().

[darren]

In VB.Net 2005, you can show a form in 1 line
My.Forms.Form1.Show

From help...
The My.Forms object provides an easy way to access an instance of each Windows Form declared in the application's project. You can also use properties of the My.Application object to access the application's splash screen and main form, and get a list of the application's open forms.