Passing System.EventArgs as parameters

[GatorBait]

Hi everyone,

I've been using VB.NET for about 6 weeks now and I keep stumbling on a
concept that I hope someone can clear up for me. Each event of a
control has 2 parameters, sender and e....I am not understanding what
the purpose of those parameters are. Can someone clear that up?

Along those lines, I also don't understand how to make a call to a
Click event...what are you supposed to pass in?

In a program that I am working on I need to draw a border around a
panel. I did some research and found some code that will do just that
(sorry if it pastes ugly):

Private Sub PaintBorder(ByVal sender As Object, ByVal e As
System.Windows.Forms.PaintEventArgs)
ControlPaint.DrawBorder(e.Graphics, e.ClipRectangle,
Color.Black, 3, ButtonBorderStyle.Solid, Color.Black, 3,
ButtonBorderStyle.Solid, Color.Black, 3, ButtonBorderStyle.Solid,
Color.Black, 3, ButtonBorderStyle.Solid)
End Sub

How would I call this function if I wanted to paint a border on a panel
called Panel1???

Thank you in advance for any help!

[Dennis]

The S is the source object (Form, control, class, etc.) that fired the event.
If you want to fire the click event for a control, use
myControl.PerformClick.

In the Click event, you can access the source object's properties, methods,
etc. by:

DirectCast ( S, myControlThatFiredEventType).myControlThatFiredEve ntProperty1.

For example if a Button click event is fired from a form, you can set the
form''s backcolor in the click event as follows:

DirectCast(S, Form).BAckColor = Color.Red

Hope this helps.

--
Dennis in Houston
"GatorBait" wrote:

Hi everyone,

I've been using VB.NET for about 6 weeks now and I keep stumbling on a
concept that I hope someone can clear up for me. Each event of a
control has 2 parameters, sender and e....I am not understanding what
the purpose of those parameters are. Can someone clear that up?

Along those lines, I also don't understand how to make a call to a
Click event...what are you supposed to pass in?

In a program that I am working on I need to draw a border around a
panel. I did some research and found some code that will do just that
(sorry if it pastes ugly):

Private Sub PaintBorder(ByVal sender As Object, ByVal e As
System.Windows.Forms.PaintEventArgs)
ControlPaint.DrawBorder(e.Graphics, e.ClipRectangle,
Color.Black, 3, ButtonBorderStyle.Solid, Color.Black, 3,
ButtonBorderStyle.Solid, Color.Black, 3, ButtonBorderStyle.Solid,
Color.Black, 3, ButtonBorderStyle.Solid)
End Sub

How would I call this function if I wanted to paint a border on a panel
called Panel1???

Thank you in advance for any help!

[Dennis]

One more answer to your last question:

Try Panel1.Invalidate..this will trigger the Paint Event.
--
Dennis in Houston
"GatorBait" wrote:

Hi everyone,

I've been using VB.NET for about 6 weeks now and I keep stumbling on a
concept that I hope someone can clear up for me. Each event of a
control has 2 parameters, sender and e....I am not understanding what
the purpose of those parameters are. Can someone clear that up?

Along those lines, I also don't understand how to make a call to a
Click event...what are you supposed to pass in?

In a program that I am working on I need to draw a border around a
panel. I did some research and found some code that will do just that
(sorry if it pastes ugly):

Private Sub PaintBorder(ByVal sender As Object, ByVal e As
System.Windows.Forms.PaintEventArgs)
ControlPaint.DrawBorder(e.Graphics, e.ClipRectangle,
Color.Black, 3, ButtonBorderStyle.Solid, Color.Black, 3,
ButtonBorderStyle.Solid, Color.Black, 3, ButtonBorderStyle.Solid,
Color.Black, 3, ButtonBorderStyle.Solid)
End Sub

How would I call this function if I wanted to paint a border on a panel
called Panel1???

Thank you in advance for any help!