A Question on VB Classes

[Brian]

Can some one please tell me what I'm doing wrong. I'm trying to create
a class called Dog, but Visual Basic tells me that I can't enter
Wolf.age....why is this?

Public Class Form1
Public Class DOG
Dim COLOUR As String
Dim AGE As Integer
Dim NAME As String

End Class
Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10

End Sub
End Class

Regards Brian

[Robinson]

Public Class Form1

Public Class DOG
Dim COLOUR As String
Dim AGE As Integer
Dim NAME As String

End Class
Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10

End Sub
End Class

Regards Brian

Your "Dim" isn't public by default, try this instead:

Public COLOUR As String
Public AGE As Integer
Public NAME As String

[rowe_newsgroups]

Because the property variables aren't visible. Declare them with the
public keyword instead of dim (which is private by default). i.e. The
following should work just fine.

Public Class Form1
Public Class DOG
Public COLOUR As String
Public AGE As Integer
Public NAME As String

End Class

Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10

End Sub
End Class

Brian wrote:

Can some one please tell me what I'm doing wrong. I'm trying to create
a class called Dog, but Visual Basic tells me that I can't enter
Wolf.age....why is this?

Public Class Form1
Public Class DOG
Dim COLOUR As String
Dim AGE As Integer
Dim NAME As String

End Class
Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10

End Sub
End Class

Regards Brian

[GhostInAK]

Brian,

While it may work, it's ugly as sin. You should separate your DOG class
out into a different file. Also, instead of using fields publicly you should
make them private and provide public properties instead.

-Boo

Because the property variables aren't visible. Declare them with the
public keyword instead of dim (which is private by default). i.e. The
following should work just fine.

Public Class Form1
Public Class DOG
Public COLOUR As String
Public AGE As Integer
Public NAME As String
End Class

Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10
End Sub
End Class
Brian wrote:

>Can some one please tell me what I'm doing wrong. I'm trying to
create a class called Dog, but Visual Basic tells me that I can't
enter Wolf.age....why is this?

Public Class Form1
Public Class DOG
Dim COLOUR As String
Dim AGE As Integer
Dim NAME As String
End Class

Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventAr gs) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10
End Sub
End Class
Regards Brian

[Spam Catcher]

"Robinson" <it************ *****@nowmyinbo xisfull.comwrot e in news:eeoj9j
$j************* @news.demon.co. uk:

Your "Dim" isn't public by default, try this instead:

Public COLOUR As String
Public AGE As Integer
Public NAME As String

Even better declare the variables as properties : )

[Dennis]

Why separate the dog class to a different file...moving it to after the end
of the form class should work also.

Why use a private variable then a property to read/write it if no special
actions are needed for the read and write?

--
Dennis in Houston
"GhostInAK" wrote:

Brian,

While it may work, it's ugly as sin. You should separate your DOG class
out into a different file. Also, instead of using fields publicly you should
make them private and provide public properties instead.

-Boo

Because the property variables aren't visible. Declare them with the
public keyword instead of dim (which is private by default). i.e. The
following should work just fine.

Public Class Form1
Public Class DOG
Public COLOUR As String
Public AGE As Integer
Public NAME As String
End Class

Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10
End Sub
End Class
Brian wrote:

Can some one please tell me what I'm doing wrong. I'm trying to
create a class called Dog, but Visual Basic tells me that I can't
enter Wolf.age....why is this?

Public Class Form1
Public Class DOG
Dim COLOUR As String
Dim AGE As Integer
Dim NAME As String
End Class

Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10
End Sub
End Class
Regards Brian

[rowe_newsgroups]

Why use a private variable then a property to read/write it if no special

actions are needed for the read and write?

The dog class isn't a real good example, but normally you want more
control over the property (validation for example). Just like Option
Strict On isn't always needed (and requires more code) using properties
instead of variables is just good programming practice. IMHO it
improves the readablity of the code and makes it much much easier to
update and/or modify.

Why separate the dog class to a different file...moving it to after the end
of the form class should work also.

Again, this is not a good example but moving it to a different file is
mainly for code reuse (OOP). If this was a more "advanced" class that
would be used in multiple solutions, being in the form's class file
wouldn't be a good idea. You would have to add an unneeded and unwanted
class (the form class) just to get to the advanced class. In my opinion
you shouldn't group unrelated classes in the same file.

Pretty much the suggestions were mainly to teach someone new to vb
classes good programming practices, not to say that what he had was
wrong.

Hope that clarifies some things,

Seth Rowe

Dennis wrote:

Why separate the dog class to a different file...moving it to after the end
of the form class should work also.

Why use a private variable then a property to read/write it if no special
actions are needed for the read and write?

--
Dennis in Houston
"GhostInAK" wrote:

Brian,

While it may work, it's ugly as sin. You should separate your DOG class
out into a different file. Also, instead of using fields publicly you should
make them private and provide public properties instead.

-Boo

Because the property variables aren't visible. Declare them with the
public keyword instead of dim (which is private by default). i.e. The
following should work just fine.
>
Public Class Form1
Public Class DOG
Public COLOUR As String
Public AGE As Integer
Public NAME As String
End Class
>
Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10
End Sub
End Class
Brian wrote:
>
>Can some one please tell me what I'm doing wrong. I'm trying to
>create a class called Dog, but Visual Basic tells me that I can't
>enter Wolf.age....why is this?
>>
>Public Class Form1
>Public Class DOG
>Dim COLOUR As String
>Dim AGE As Integer
>Dim NAME As String
>End Class
>>
>Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
>System.EventAr gs) Handles Button1.Click
>Dim WOLF As New DOG
>WOLF.AGE = 10
>End Sub
>End Class
>Regards Brian
>>

[Ray Cassick \(Home\)]

Yeah...

Public members are baaaaaaaaaaaaaa aaaaaaaaaaaaaaa d.

Think encapsulation.

If I ever found one of my coders doing Public x As Integer in a class I
would force them to clean the bathrooms for a week.

"Spam Catcher" <sp**********@r ogers.comwrote in message
news:Xn******** *************** ***********@127 .0.0.1...

"Robinson" <it************ *****@nowmyinbo xisfull.comwrot e in news:eeoj9j
$j************* @news.demon.co. uk:

>Your "Dim" isn't public by default, try this instead:

Public COLOUR As String
Public AGE As Integer
Public NAME As String

Even better declare the variables as properties : )

[Brian]

Spam Catcher <sp**********@r ogers.comwrote:

>"Robinson" <it************ *****@nowmyinbo xisfull.comwrot e in news:eeoj9j
$j************ *@news.demon.co .uk:

>Your "Dim" isn't public by default, try this instead:

Public COLOUR As String
Public AGE As Integer
Public NAME As String

Even better declare the variables as properties : )

Can you give me an example using my DOG Class please.
I'm new to this side of programming so I'm not certain what you mean
by declaring the variables as properties.

Regards Brian

[Brian]

Thanks for all your repies.

If someone could give me easy to follow examples of using Classes in
Visual Basic then that would be helpful.
Perhaps a web address the has code for a VB program that I could
download or if you have code that could be ziped up and sent to me by
e-mail for me to study then this would be helpful to learn more abolut
how to use classes in VB program code thanks.

Regards Brian


Brian <bc****@es.co.n zwrote:

>Can some one please tell me what I'm doing wrong. I'm trying to create
a class called Dog, but Visual Basic tells me that I can't enter
Wolf.age....wh y is this?

Public Class Form1
Public Class DOG
Dim COLOUR As String
Dim AGE As Integer
Dim NAME As String

End Class
Public Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventAr gs) Handles Button1.Click
Dim WOLF As New DOG
WOLF.AGE = 10

End Sub
End Class

Regards Brian