Question

So what I would like to do is something I see pretty frequently on webforms etc., basically in my webform I want to grant the user the ability to add more information as is necessary. For example I ask for a word but I want to allow the entry of multiple words by having a button to reveal an additional textbox each time it is clicked. Right now how I am trying to implement it is by creating 3 textboxes (and buttons corresponding to each one) leaving the first one visible but hiding the rest. The idea would be then that a global varible which track which textbox should be revealed and then I run a switch statement on that and reveal the appropriate box:

<asp:TextBox ID="textBoxNewCanonical" runat="server"></asp:TextBox>
<asp:Button runat="server" ID="buttonFind" Text="Find" Visible="false" OnClick="buttonFind_OnClick" />
<asp:TextBox ID="textBoxNewCanonical1" Visible="false" runat="server"></asp:TextBox>
<asp:Button runat="server" ID="buttonFind1" Text="Find" Visible="false" OnClick="buttonFind_OnClick" />
<asp:TextBox ID="textBoxNewCanonical2" Visible="false" runat="server"></asp:TextBox>
<asp:Button runat="server" ID="buttonFind2" Text="Find" Visible="false" OnClick="buttonFind_OnClick" />
<asp:Button runat="server" ID="btnMultipleCanonical" Text="Choose Another Canoical" OnClick="buttonChooseAnother_Click" />

and here is the buttonChooseAnother_Click

protected void buttonChooseAnother_Click(object sender, EventArgs e)
{
    switch(CanonicalNum)
    {
        case 0:
            textBoxNewCanonical1.Visible = true;
            buttonFind1.Visible = true;
            break;
        case 1:
            textBoxNewCanonical2.Visible = true;
            buttonFind2.Visible = true;
            break;
        default:
            break;
    }
    CanonicalNum = CanonicalNum+1;
}

CanonicalNum is set to 0 to start It seems like this should work but what ends up happening is when I click the button it just shows textBoxNewCanonical1 and then doesn’t do anything else the next time I click.
So my question is two-fold
1. Can anyone tell me what might be wrong with my code and how to fix it
2. If there is a better way to do it I would be happy to hear it

A couple things you might want to know is that I need to be able to access the buttons currently I also use a switch statement to handle them in one event handler. Also I need access to the text fields so that I can fill in a value upon another button click event.

Edit: Its a subpage of a Masterpage just fyi.

Answer 1

The button click will cause postbacks, which will reset CanonicalNum to 0 when the page reloads. I would use Session to store CanonicalNum:

In your page_load method, add this:

if (!Page.IsPostBack)
{
    CanonicalNum = 0;
    Session["CanonicalNum"] = CanonicalNum;
}
else
{
    CanonicalNum = (int)Session["CanonicalNum"];
}

In your button click event, update the Session object with the new value after you increment CanonicalNum:

Session["CanonicalNum"] = CanonicalNum;

If you want the textboxes to stay visible, you’ll need to update your buttonChooseAnother_Click to handle this, otherwise the ones that don’t match CanonicalNum will be set back to Visible = “false” on postack:

protected void buttonChooseAnother_Click(object sender, EventArgs e) 
{     

    switch(CanonicalNum)     
    {         
        case 0:             
            textBoxNewCanonical1.Visible = true;             
            buttonFind1.Visible = true;
            break;         
        case 1:
            textBoxNewCanonical1.Visible = true;
            buttonFind1.Visible = true;             
            textBoxNewCanonical2.Visible = true;
            buttonFind2.Visible = true;             
            break;         
        default:             
            break;     
    }     

    CanonicalNum = CanonicalNum+1; 
    Session["CanonicalNum"] = CanonicalNum;

}

I think you may want to revisit what you’re trying to accomplish, as there’s probably a better way to do it.