user-defined data type capabilities

It seems I use Microsoft Visual Basic 6.5 from Microsoft Excel 2003.

I've just introduced my first user-defined data type (UDT) to a module.
I found it greatly simplified passing parameters.

Private Type Journey
    Depart As String
    Arrive As String
End Type

What can I do with such UDTs?
1) Declare functions and scalar, array, and parameter variables.
2) Assign e.g. Dim A as UDT, B as UDT: A = B
3) Not compare variables. e.g. if UDT0 = UDT1 ... gets an error.

What else can UDTs be used for?

When, in the Visual Basic Editor (VBE), I hover over code referencing a
variable or expression of a predefined type (Byte, Boolean, Integer,
....), the VBE displays its value.
Can this be extended to UDTs?
if so, how?

I assume such code would avoid the type mismatch I get if I do "?UDT" in
the immediate window.
-- 
Walter Briscoe
0
Walter
11/22/2009 12:25:53 PM
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Look in the VBA help after searching for:
Type Statement

RBS


"Walter Briscoe" <wbriscoe@nospam.demon.co.uk> wrote in message 
news:HbzdCwXR3SCLFwGA@freenetname.co.uk...
> It seems I use Microsoft Visual Basic 6.5 from Microsoft Excel 2003.
>
> I've just introduced my first user-defined data type (UDT) to a module.
> I found it greatly simplified passing parameters.
>
> Private Type Journey
>    Depart As String
>    Arrive As String
> End Type
>
> What can I do with such UDTs?
> 1) Declare functions and scalar, array, and parameter variables.
> 2) Assign e.g. Dim A as UDT, B as UDT: A = B
> 3) Not compare variables. e.g. if UDT0 = UDT1 ... gets an error.
>
> What else can UDTs be used for?
>
> When, in the Visual Basic Editor (VBE), I hover over code referencing a
> variable or expression of a predefined type (Byte, Boolean, Integer,
> ...), the VBE displays its value.
> Can this be extended to UDTs?
> if so, how?
>
> I assume such code would avoid the type mismatch I get if I do "?UDT" in
> the immediate window.
> -- 
> Walter Briscoe 

0
RB
11/22/2009 2:17:04 PM
You can pretty much do anything with a UDT that you can with any other 
variable.  You need to remember that the various predefined types you use as 
members of your UDT now become properties of any variables you define, via 
Dim, as a UDT.  Perhaps these simple examples will help you get a better 
picture of how it works.  One uses a simple variable defined as a UDT named 
myUDT, and the second uses an array defined as the same UDT type.

You need to remember to use the properties when referencing any variable 
you've declared as one of your UDTs; that will prevent errors when doing 
comparisons and when trying to print their values, i.e.
If UDT1.Property1 = UDT2.Property1 Then
or
? UDT1.Property5
in the Immediate window.

Type myUDT
  depart As Date
  arrive As Date
  distance As Integer
End Type

Sub CalculateMPH()
  Dim myTrip As myUDT
  
  myTrip.depart = "1/1/09 12:00:00"
  myTrip.arrive = "1/1/09 12:45:00"
  myTrip.distance = 38
  MsgBox "MPH for the trip was: " & myTrip.distance / ((myTrip.arrive - 
myTrip.depart) * 24)
End Sub
  
Sub CalculateTripLegs()
 'an array of user defined type myUDT
  Dim myTrip(1 To 10) As myUDT
  
  myTrip(1).depart = "1/1/09 12:00:00"
  myTrip(1).arrive = "1/1/09 12:45:00"
  myTrip(1).distance = 38
  MsgBox "MPH for the trip was: " & myTrip(1).distance / ((myTrip(1).arrive 
- myTrip(1).depart) * 24)
End Sub


"Walter Briscoe" wrote:

> It seems I use Microsoft Visual Basic 6.5 from Microsoft Excel 2003.
> 
> I've just introduced my first user-defined data type (UDT) to a module.
> I found it greatly simplified passing parameters.
> 
> Private Type Journey
>     Depart As String
>     Arrive As String
> End Type
> 
> What can I do with such UDTs?
> 1) Declare functions and scalar, array, and parameter variables.
> 2) Assign e.g. Dim A as UDT, B as UDT: A = B
> 3) Not compare variables. e.g. if UDT0 = UDT1 ... gets an error.
> 
> What else can UDTs be used for?
> 
> When, in the Visual Basic Editor (VBE), I hover over code referencing a
> variable or expression of a predefined type (Byte, Boolean, Integer,
> ....), the VBE displays its value.
> Can this be extended to UDTs?
> if so, how?
> 
> I assume such code would avoid the type mismatch I get if I do "?UDT" in
> the immediate window.
> -- 
> Walter Briscoe
> .
> 
0
Utf
11/22/2009 3:05:03 PM
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