it took me ages to find it. i googled "add controls at runtime" and not one single result gave me the intstructions on how to add code to the controls. kinda useless with no code, ehh? all results only told me how to add the control, that's it. well, this result is different. i will teach you firstly how to add controls at runtime, then how to apply code to them at runtime


firstly, add the controls:

create a new windows forms application
then double click on the form and type this:

Dim mybutton As New Button
        mybutton.Name = "button1"
        mybutton.Location = New Point(20, 20)
mybutton.text = "click me"
        Me.Controls.Add(mybutton)
        With mybutton
            AddHandler .Click, AddressOf button1_click
        End With

now run it. do you have a button on the form? if yes, excellent. if not, you made a mistake. try again

now how to add code? you may have noticed that when you double click on any control, it says private sub button1_click(blah, blah, blah) Handles button1.click
where it says handles button1.click is what determines when the code executes under what event for what control (in this case the click event for the button1). this won't work when adding code at runtime.

did you notice in the above example i added a with event, and addHandler? this is what creates the handler (same as Handles button1.click)

now we add the code for the runtime control

private sub button1_click()
MsgBox("you have added code and a control at runtime!")
end sub

above, the addressOf button1_click tells the program to execute the sub button1_click when the button is clicked on (as determined by .click)


but i know what you're thinking! your thinking "why would we even BOTHER doing this at runtime? isn't it easier to do it at design-time in the first place?"

yes it is, providing your not writing a plugin. plugins are code based, not GUI (also reffered to as WYSIWYG). to update existing forms using plugins, you need to use this method.

You can't add code at runtime because VB code has to be compiled. However, it is still very useful to be able to add controls at runtime. For example, I wrote a version of Scattergories last summer. The number of players can vary from game to game so it is convenient to be able to generate controls for the input and display for the players at runtime. If you have an application that uses external programs you could add buttons at runtime to link to these tools. The buttons can all use the same handler but invoke different programs depending on what the user entered when the tool was added.

Yea so its basically like compiling new code but from external side of the Original app if im right

Right. And that can't be done from inside your application.

Yea like firefox uses separate app for its plugins

But it uses almost 100 mb to do it :icon_lol:
Epic fail :icon_mrgreen:

or maybe its just container that might make the odds better but still 100 mb not right :D

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