Handling radio buttons

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Oct 30th, 2003, 11:53 PM
mendhak

Handling radio buttons
I put three radio buttons on a form. Then, I wanted to handle them all from a single sub, so I made a Sub like this:
VB Code:
```
Private Sub RadioArray_Checked(ByVal sender As Object, ByVal e As System.EventArgs) Handles RadioButton1.Click, RadioButton2.Click, RadioButton3.Click
 
 
End Sub
```
Now, how can I determine which radio button was clicked, and determine it's value as well?

TIA.

you'd be best adding a handler for all the buttons, rather that having a long sub ( saying Handles radiobutton1 , radiobutton2 .....) , here's a quick example...

VB Code:

[Color=Blue]Private[/COLOR] [Color=Blue]WithEvents[/COLOR] RadioArray [Color=Blue]As[/COLOR] RadioButton
 
    [Color=Blue]Private[/COLOR] [Color=Blue]Sub[/COLOR] Form1_Load([Color=Blue]ByVal[/COLOR] sender [Color=Blue]As[/COLOR] System.Object, [Color=Blue]ByVal[/COLOR] e [Color=Blue]As[/COLOR] System.EventArgs) [Color=Blue]Handles[/COLOR] [Color=Blue]MyBase[/COLOR].Load
        [Color=Blue]Dim[/COLOR] rdBtn [Color=Blue]As[/COLOR] Control
        [Color=Blue]For[/COLOR] [Color=Blue]Each[/COLOR] rdBtn [Color=Blue]In[/COLOR] [Color=Blue]MyBase[/COLOR].Controls
            [Color=Blue]If[/COLOR] [Color=Blue]TypeOf[/COLOR] rdBtn [Color=Blue]Is[/COLOR] RadioButton [Color=Blue]Then
[/COLOR]                [Color=Blue]AddHandler[/COLOR] rdBtn.Click, [Color=Blue]AddressOf[/COLOR] RadioArray_Click
                [Color=Green]'///[/COLOR] [Color=Green]all[/COLOR] [Color=Green]radiobutton[/COLOR] [Color=Green]clicks[/COLOR] [Color=Green]now[/COLOR] [Color=Green]handled[/COLOR] [Color=Green]by[/COLOR] [Color=Green]one[/COLOR] [Color=Green]sub[/COLOR] [Color=Green].[/COLOR] [Color=Green]
[/COLOR]            [Color=Blue]End[/COLOR] [Color=Blue]If
[/COLOR]        [Color=Blue]Next
[/COLOR]    [Color=Blue]End[/COLOR] [Color=Blue]Sub
 
[/COLOR]    [Color=Blue]Private[/COLOR] [Color=Blue]Sub[/COLOR] RadioArray_Click([Color=Blue]ByVal[/COLOR] sender [Color=Blue]As[/COLOR] [Color=Blue]Object[/COLOR], [Color=Blue]ByVal[/COLOR] e [Color=Blue]As[/COLOR] System.EventArgs) [Color=Blue]Handles[/COLOR] RadioArray.Click
        [Color=Blue]Dim[/COLOR] btn [Color=Blue]As[/COLOR] RadioButton = [Color=Blue]DirectCast[/COLOR](sender, RadioButton)
        [Color=Blue]Select[/COLOR] [Color=Blue]Case[/COLOR] btn.Name
            [Color=Blue]Case[/COLOR] "RadioButton1"
                [Color=Green]'///[/COLOR] [Color=Green]carry[/COLOR] [Color=Green]out[/COLOR] [Color=Green]code[/COLOR] [Color=Green]for[/COLOR] [Color=Green]radiobutton1[/COLOR] [Color=Green],[/COLOR] [Color=Green][/COLOR] [Color=Green]eg:
[/COLOR]                [Color=Blue]If[/COLOR] btn.Checked [Color=Blue]Then
[/COLOR]                    [Color=Green]'///[/COLOR] [Color=Green]do[/COLOR] [Color=Green]stuff[/COLOR] [Color=Green]because[/COLOR] [Color=Green]it's[/COLOR] [Color=Green]checked[/COLOR] [Color=Green].[/COLOR] [Color=Green]
[/COLOR]                [Color=Blue]Else
[/COLOR]                    [Color=Green]'///[/COLOR] [Color=Green]it's[/COLOR] [Color=Green]not[/COLOR] [Color=Green]checked[/COLOR] [Color=Green].[/COLOR] [Color=Green]
[/COLOR]                [Color=Blue]End[/COLOR] [Color=Blue]If
[/COLOR]            [Color=Blue]Case[/COLOR] "RadioButton2"
                [Color=Green]'///[/COLOR] [Color=Green]and[/COLOR] [Color=Green]so[/COLOR] [Color=Green]on[/COLOR] [Color=Green].[/COLOR] [Color=Green][/COLOR] [Color=Green].[/COLOR] [Color=Green][/COLOR] [Color=Green].[/COLOR] [Color=Green]
[/COLOR]        [Color=Blue]End[/COLOR] [Color=Blue]Select
[/COLOR]    [Color=Blue]End[/COLOR] [Color=Blue]Sub[/COLOR]

Oct 31st, 2003, 12:41 AM
mendhak
That's a great snippet you just gave.

After some hair pulling, I came up with this:
VB Code:
```
Private Sub RadioArray_Checked(ByVal sender As Object, ByVal e As System.EventArgs) Handles RadioButton1.Click, RadioButton2.Click, RadioButton3.Click
 
        Dim a As RadioButton
        a = CType(sender, RadioButton)
        MessageBox.Show("you clicked " & a.Name & "")
 
    End Sub
```
But obviously yours is better.

Uhm... I'm still unaware of so many of these little methods that people use to accomplish stuff, while I was great at VB6. Can you suggest some good book for me? More practical examples rather than theoretical stuff. I already have Dan Appleman's "Moving to VB.NET", but it's very theoretical.

Thank you.
Oct 31st, 2003, 12:48 AM
mendhak
VB Code:
```
AddHandler rdBtn.Click, AddressOf RadioArray_Click
```
What is this? It's not a function, because parantheses cause errors...
Oct 31st, 2003, 12:51 AM
dynamic_sysop
no problem :) little things you will pick up on ( as i did when i changed from vb6 ) are like this...
in vb6 you had to Dim first , eg:
VB Code:
```
Dim a As RadioButton
a = CType(sender, RadioButton)
```
in vb.net you can Dim and also Set the item in one line , eg:
VB Code:
```
Dim a As RadioButton = CType(sender, RadioButton)
```
Oct 31st, 2003, 01:02 AM
mendhak

You did a DirectCast, and I did a CType. Any difference or issues?
Oct 31st, 2003, 01:19 AM
MrPolite

Quote:

Originally posted by mendhak
You did a DirectCast, and I did a CType. Any difference or issues?

Ctype is for smokers
DirectCast is faster...
Oct 31st, 2003, 01:22 AM
mendhak

Quote:

Originally posted by MrPolite
Ctype is for smokers
DirectCast is faster...

KHAFOSHE!! :D

Yeah, well, enjoy all the fumes approaching you. You'll be screaming in them soon. :afrog:
Oct 31st, 2003, 01:22 AM
MrPolite

ok DirectCast needs a reference type. Ctype works with value types too I guess.

edit: ok this gives you an error

Dim a as integer = DirectCast("1", Integer)

there is more to it though, I cant remember