What is the purpose of private sub code in visual basic?

Answer 1

Private is a keyword that tells visual basic what the access level of the variable or procedure it is declaring will be within your application, and as such what code has permission to read it and write to it (or call it).

You would use private on variables and procedures you wish to expose only to the class in which they are actually in, the ability to correctly define public, private and protected (etc.) access levels for code is a primary principle of object oriented programming.

When you declare a variable you can do any of the following, for this example, the following three variables are all declared on one form (Form1):

Dim intVariable1 As Integer

Public intVariable2 As Integer

Private intVariable3 As Integer

All three are integer variables, the difference comes in what can and cannot access them. Dim and Private are equivalent, one and the same, they can only be accessed and manipulated within the form itself.

However, intVariable2 is declared as public, which means that for example, if we created another form (Form2) with the following code behind it declaring a new copy of form 1:

Private oForm1 As New Form1

oForm1.intVariable2 = 87

We can change and access the second variable from another form, however since the other two variables are declared Dim and Private they cannot be accessed from any other location than within form1 itself.

Hope this clarifies it a bit for you.

Answer 2

"Sub" stands for "Subroutine". It is used like the "void" keyword in java and c#.

Answer 3

A subroutine is a procedure that does not return a value to its caller. Only functions can return values to their callers.

Answer 4

sub procedure.

Answer 5

I do not no

Answer 6

Study the VB 2010 code below and answer questions that follow

Private Sub BtnFOR_Click...

Dim i As Integer

For i = 1 To 25 Step 5

LstFOR.Items.Add(i & " " & i*10)

Next

End Sub