HOW TO: dynamically add control in VB.NET?

[owenrb]

Dear all,

I have this question. Is it possible for VB.NET to add or dynamically create control during run-time? And, how would I add event handler for these dynamically created controls.
Please advice me on this. Any help you may have will be very much appreciated. Thanks in advance.


Best Regards,

Owen/

[ITGURU]

Dear Owen,

I think there is nothing impossible in this world and same apply when we programming in any language.

Here below is the solution for your problem:

1. Add any procedure for event handling of the control like as follows:


Protected Sub button1_Click(sender As Object, e As System.EventArgs)
' Go to the previous item in the Customer list.
messagebox.show("Button Pressed")
End Sub



2. Add following line immediately after the following lines

Public Class Form1
Inherits Form

in the form:


Private button1 As Button



2. Add following line of code in InitializeComponent method of the form (you can find InitializeComponent method when you expand #Region " Windows Form Designer generated code "


With Me
.components = New Container
.button1 = New Button

With .button1
.Location = New Point(24, 16)
.Size = New Size(64, 24)
.Text = "<"
AddHandler button1.click, AddressOf button1_Click
End With

With .Controls
.Add(button1)
End With
End With


Hope this will solve your problem.

Regards

Gurdarshan Singh

[Rube74]

Yeah, ITGURU's solution is pretty much how you would want to do it. You can set up functions which will create the widget of your choice and add those to a form, panel, or other container. Then, you can dynamically run those functions at run-time (all you really have to pass is a location and a size). The best place to start would probably be by looking at the ControlCollections, and, in particular, the Add method for these ControlCollections.

Adding the event handler is a little trickier, but I would assume that you should be able to do that in your widget-creation functions as well.

[owenrb]

Thanks ITGURU, it really works. That was very CLEVER.

Then, I implement this array of push button.
But I have problem determining which of those buttons is being pushed, since there were no index variable exposed inside button1_Click() sub module. Any advice?

Again, thank you very much.


Regards,

Owen/

[Rube74]

You could try using the Control Collection index for the button. For example, if it's the button is the first form element on the form, you could say:

AddHandler Me.Controls(0).Click(), AddressOf button1_Click

This index starts at 0 and increases sequentially with each new element you put on the form.

[ITGURU]

hello,

Please try using Text property of the Button control for finiding which control is clicked and you can find the detail by using following code:

Write following line for validating the control to whom user clicked in the Event which is assigned to the control:

if CType(sender, Button).Text) = "Button1" then
else
if CType(sender, Button).Text) = "Button3" then
endif
endif


Hope this will solve your problem.

[owenrb]

That's a good suggestion, ITGURU. Thanks.
Thank you Rube74.
Have a nice day to both of you.


Best Regards,

Owen/