newby VB arrays

[Boni]

Dear all,
How can I add something to the VB arrays after the initialization.
dim _points() as System.Drawing.points
If it is not possible how can I pass into function, with VB array as an
argument the .NET array.
I.e.
sub func(byval _points() as System.Drawing.points)
....
end sub
sub Main
dim _Array as arraylist
_array.add(..)
_array.add(..)
_array.add(..)
func(_array) <---- fails

What is the correct syntax?
Thanks,
Boni

[Dennis]

You are not passing the same type parameter, i.e., an arraylist being passed
to a function expecting an array. Try the following:

sub func(byval _points as Arraylist)

Then in the function when you use an element of _points;

dim b as point

b=directcast(_points(1),point)

You can then use b directly as a point or cast the _points array element to
a point type each time you need to use of _points elements.
--
Dennis in Houston
"Boni" wrote:

Dear all,
How can I add something to the VB arrays after the initialization.
dim _points() as System.Drawing.points
If it is not possible how can I pass into function, with VB array as an
argument the .NET array.
I.e.
sub func(byval _points() as System.Drawing.points)
....
end sub
sub Main
dim _Array as arraylist
_array.add(..)
_array.add(..)
_array.add(..)
func(_array) <---- fails

What is the correct syntax?
Thanks,
Boni

[Cor Ligthert [MVP]]

Boni,

\\\
sub func(byval ThisPoints as Arraylist)
dim mypoint as point = DirectCast(ThisPoints(0), System.Drawing.Points)
end sub
sub Main
dim Arl as new arraylist
Arl.Add(..points)
Arl.add(..)
Arl.add(..)
func(Arl)
///
I hope this helps,

Cor

[Boni]

Dear Sirs,
I thing there is a missunderstanding.
I didn' said, that I can't change func. It was not written by me (example of
func is Graphics.FillPolygon(brush, _points).
But I need to create the array of points dsynamically. Is it possible
somehow?
Thanks,
Boni

"Dennis" <De****@discussions.microsoft.com> schrieb im Newsbeitrag
news:52**********************************@microsof t.com...

You are not passing the same type parameter, i.e., an arraylist being
passed
to a function expecting an array. Try the following:

sub func(byval _points as Arraylist)

Then in the function when you use an element of _points;

dim b as point

b=directcast(_points(1),point)

You can then use b directly as a point or cast the _points array element
to
a point type each time you need to use of _points elements.
--
Dennis in Houston
"Boni" wrote:

Dear all,
How can I add something to the VB arrays after the initialization.
dim _points() as System.Drawing.points
If it is not possible how can I pass into function, with VB array as an
argument the .NET array.
I.e.
sub func(byval _points() as System.Drawing.points)
....
end sub
sub Main
dim _Array as arraylist
_array.add(..)
_array.add(..)
_array.add(..)
func(_array) <---- fails

What is the correct syntax?
Thanks,
Boni

[Herfried K. Wagner [MVP]]

"Boni" <oilia@nospam> schrieb:

How can I add something to the VB arrays after the initialization.
dim _points() as System.Drawing.points
If it is not possible how can I pass into function, with VB array as an
argument the .NET array.
I.e.
sub func(byval _points() as System.Drawing.points)
...
end sub
sub Main
dim _Array as arraylist
=> 'As New ArrayList()'.
_array.add(..)
_array.add(..)
_array.add(..)
func(_array) <---- fails

What is the correct syntax?

The size of an array cannot be altered after the array is created. However,
you can create a new array of appropriate size and copy the data from the
old array over to the new array. This operation can be simplified by using
'ReDim Preserve' (see documentation).

In the sample above there is nothing wrong with an arraylist. You an create
an array based on the arraylist and pass the array to the function:

\\\
func(DirectCast(_array.ToArray(GetType(Point)), Point()))
///

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://classicvb.org/petition/>

[Cor Ligthert [MVP]]

> Dear Sirs,

I thing there is a missunderstanding.
I didn' said, that I can't change func. It was not written by me (example
of func is Graphics.FillPolygon(brush, _points).

Why are you asking than this what is bellow and not what is above.

If it is not possible how can I pass into function, with VB array as an
argument the .NET array.

Maybe can you than be more clear, if you want a variable fixed array of
points it is more work than that you want a real fixed array of points.

Cor

[Cor Ligthert [MVP]]

Boni,

This I never tried, however I got this idea, I think that it is more
eficient than we have ever showed it in this newsgroup.

\\\
Sub func(ByVal ThisPoints() As System.Drawing.Point)
End Sub
Sub test()
Dim Arl As New ArrayList
Arl.Add(New Point(1, 2))
Arl.Add(New Point(1, 2))
Dim mPoint(Arl.Count - 1) As System.Drawing.Point
Arl.CopyTo(mPoint)
func(mPoint)
End Sub
///

I hope this helps,

Cor

[Herfried K. Wagner [MVP]]

"Cor Ligthert [MVP]" <no************@planet.nl> schrieb:

This I never tried, however I got this idea, I think that it is more
eficient than we have ever showed it in this newsgroup.

\\\
Sub func(ByVal ThisPoints() As System.Drawing.Point)
End Sub
Sub test()
Dim Arl As New ArrayList
Arl.Add(New Point(1, 2))
Arl.Add(New Point(1, 2))
Dim mPoint(Arl.Count - 1) As System.Drawing.Point
Arl.CopyTo(mPoint)
func(mPoint)
End Sub

Mhm... I still prefer this one:

\\\
Dim a As New ArrayList()
a.Add(New Point(10, 10))
a.Add(New Point(20, 20))
a.Add(New Point(30, 30))
Dim Points() As Point = DirectCast(a.ToArray(GetType(Point)), Point())
///

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://classicvb.org/petition/>

[Cor Ligthert [MVP]]

Herfried,

Than would be even better in this case

\\\
func(DirectCast(a.ToArray(GetType(Point)), Point()))
///

However maybe is my sample easier to understand.

:-)

Cor

[Herfried K. Wagner [MVP]]

"Cor Ligthert [MVP]" <no************@planet.nl> schrieb:

Than would be even better in this case

\\\
func(DirectCast(a.ToArray(GetType(Point)), Point()))
///
ACK. This was my initial suggestion.
However maybe is my sample easier to understand.

That might be true... :-).

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://classicvb.org/petition/>

[Cor Ligthert [MVP]]

Herfried,

You are right, I thought it were the parameters from the function it self.

And as you know I can say Sorry,

:-)

Cor

[Boni]

Dear Cor,
Let's have following concrete example.
I want to create an array of points dynamically and than use it in
FillPolygon.The signature of FillPolygon is(brush, point())
How can I convert dynamic array of poins into an array which is required by
FillPolygone?
Did I understand you correctly, that it is not possible to use FillPolygon
if the number of points is not known at compile time?
Thank you very much for your help,
Boni
"Cor Ligthert [MVP]" <no************@planet.nl> schrieb im Newsbeitrag
news:OC**************@TK2MSFTNGP12.phx.gbl...

Dear Sirs,
I thing there is a missunderstanding.
I didn' said, that I can't change func. It was not written by me (example
of func is Graphics.FillPolygon(brush, _points).

Why are you asking than this what is bellow and not what is above.

If it is not possible how can I pass into function, with VB array as an
argument the .NET array.

Maybe can you than be more clear, if you want a variable fixed array of
points it is more work than that you want a real fixed array of points.

Cor

[Boni]

Dear Sirs,
thank you for your great help! Now the solution is very clear.
Boni