Question

I have a web application.
On my page ive got this:

<div id="myDiv" runat="server" />
//and a button that will call a method to save my inputs

on code behind i have this :

    protected override void OnLoad(EventArgs e)
{
    base.OnLoad(e);

    if (!this.IsPostBack)
    {
        .....
    }
    LoadForm(); // this will create a textbox with values inside it and a button called change
                   // into the div .
                   //when i click the button , it will create a fileupload control
                  //and add this control into the div
}

my problem is:
when i first click the button change it will change the textbox and the button to an upload control, no problem with this one, but when i click the save button, on load the page will re-pass from the LoadForm() letting my page create a textbox, while i had changed it to an upload file, how can i solve this???
I dont know if i should add more details, or its clear,
thanks in advance

private void LoadForm()
        {
            ....
            button.Click += new EventHandler(button_Click);
            this.myDiv.Controls.Add(textBox);
            this.myDiv.Controls.Add(button);
    }
void button_Click(object sender, EventArgs e)
        {
            ...
            this.myDiv.Controls.Clear();
            this.myDiv.Controls.Add(here will be the fileupload control);
    }

Answer 1

The problem is that because you are creating the file upload dynamically, for it to show up again, it has to be re-added to the page. An option here would be to always have the control on the page, just toggle the visibility.