How to persist a dynamic control (c#)

Question

As per the title, I have created a custom control.

On a certain button click event, this control is instantiated, then added to the page.

It is a dynamic con

Answer 1

You should recreate dynamic controls on every postback. The best place to do that is method CreateChildControls.

To add dynamically control after button click set in click handler some flag (persistent flag - so it should be in viewstate or in sessionstate) - it should indicate that on next page creation your control should be added to it. After this you should set ChildControlsCreated = false;
After this CreateChildControls are executed again and your control is created correctly and is persistent (till you not clear flag).

So it should be done in this way:

protected override void CreateChildControls()
{
        base.CreateChildControls();
    if (ViewState["AddControl"] == true)
        {
         Controls.Add(new MyControl() {Id = "someId" });
        }
}

And btn handler

private void OnShowControlClick(object sender, EventArgs e)
{
         ViewState["AddControl"] = true;
         ChildControlsCreated = false;
}