Adding controls in code

Patc4 · April 6th, 2010, 03:55 PM

I am trying to add some radio buttons or checkboxes or listboxes in code.
It will not be known until runtime which control, or how many instances of the control are needed.
My code:
<code>
Dim Optionr1 As RadioButton = New RadioButton()
Dim Optionr2 As RadioButton = New RadioButton()
Optionr1.Text = "text from xml file"
Panel1.Controls.Add(Optionr1)
Optionr2.Text = "other text from xml file"
Panel1.Controls.Add(Optionr2)
'This shows one radio button not both (the first one only).
'
Optionr1.Text = "text from xml file"
Panel1.Controls.Add(Optionr1)
Optionr2.Text = "other text from xml file"
Panel2.Controls.Add(Optionr2)
'This shows both radio buttons but they are not connected so one or all can be checked.
'The radio buttons need to be in the same panel to work as a group. </code>

How can I see all the radio buttons and have then work as a group please?

PeterPeiGuo · April 6th, 2010, 04:41 PM

Do something like this:

Code:

        Dim r1 = New RadioButton()
        r1.ID = "r1"
        r1.GroupName = "g1"
        Panel1.Controls.Add(r1)
        Dim r2 = New RadioButton()
        r2.ID = "r2"
        r2.GroupName = "g1"
        Panel1.Controls.Add(r2)
        Dim r3 = New RadioButton()
        r3.ID = "r3"
        r3.GroupName = "g1"
        Panel1.Controls.Add(r3)

Rod Stephens · April 6th, 2010, 09:03 PM

I think the first piece of code might be creating both controls but they're appearing on top of each other. Try adding this code after you create the second control:

Optionr2.Top = Optionr1.Bottom + 5

Patc4 · April 7th, 2010, 09:07 AM

Thanks to both people, I'll try both methods and feedback ASAP.

Patc4 · April 7th, 2010, 09:47 AM

I have tried the .top and .bottom method for the radio buttons and all my controls appear, and since they are in one panel they are automatically grouped. All works well now with my prototype. Thanks Rod.

I have tried assigning to group, but the .ID gave a run time error "Public member 'ID' on type 'RadioButton' not found." I shall work on this later as this has potential to force groups I may more research. Thanks Peter.

PeterPeiGuo · April 7th, 2010, 10:23 AM

Do you hand code your page, or use Visual Studio? My sample code was tested. If you still have issue with .ID, post your entire page, and we will see.

Rod Stephens · April 7th, 2010, 10:45 PM

I'm pretty sure the System.Windows.Forms.RadioButton class doesn't have an ID property. I think there's one in ASP.NET but that's the button's name.

In WPF, the System.Controls.RadioButton class has a GroupName property and you can use it to make RadioButtons be in the same group.

In System.Windows.Forms, two RadioButtons are in the same group if they have the same parent. If you want to do something non-obvious, you can use an invisible parent such as a Panel.

PeterPeiGuo · April 8th, 2010, 12:02 AM

Ah, just noticed that this is a forum for a book (that is not focused on ASP.Net). My example was done as ASP.Net page.

That explains all.