R – ASP.NET Passing properties to dynamically generated user controls

asp.netuser-controls

I am struggling on something that, I am sure, should be easy. I have been living in backend and winforms code for a long time, and I'm am building my first ASP.NET page in over a year, so apologies for any noobishness

I am inside a User Control on a page.

On this User Control (Parent Control) I need to embed 0 .. n child user controls in a table, where each Child User control is representative of a row in a Listbox on the Parent User Control.

On the child user control I have a few properties that need setting, such as the id of the item in the list box that it represents.

As I see it, I can either

Loop through this list box in code-behind, and try to dynamically insert table rows and child user controls into an existing tag, and set the object's properties, something I have yet to make work – the added controls just don't appear
Use the old fashion ASP trick of looping through the items in the Listbox inside <% %> tags, and embed my < uc:ChildUserControl runat="server" > tags, but I'm not able to set the required properties on the ChildUserControl (I have tried a few things, but the main issue is I can't use <% %> in server controls)
Do something else that is eluding me at present

Any ideas would be greatfully received

Best Answer

repeater control bound to the same data source as the listbox?

Related Solutions

R – Silverlight Custom User Controls and Dependancy property Issue

This is definitely a step in the right direction for allowing properties to propagate.

If this is a true custom control (derives from Control), you'd want to use a {TemplateBinding Value} plus you should probably also connect to the TextChanged event on the TextBox, after setting up the template part in the OnApplyTemplate method. That way, you can have it also update your underlying TxtValue dependency property as well.

If this is a UserControl, you may be able to use Binding, but you do have a few less options to go to. As you have it, your property changed callback function is only going in one direction: you only set the Text value, you never react to it.

Let's hope the documentation out there improves.

R – Help needed on nested web User Control event in ASP.NET

Maybe it's just me, but I've never seen controls referenced and loaded like that. Here's what I would try doing it this way (which works for me):

In your Home page, register your Slot control like this instead of referencing it like your were before:

<%@ Register TagName="Slot" TagPrefix="cc" Src="~/Slot.ascx" %>

And then add the control to your page with:

<cc:Slot ID="SlotControl" runat="server" />

Now in Slot.ascx, register and include the Ray control:

<%@ Register TagName="Ray" TagPrefix="cc" Src="~/Ray.ascx" %>

<cc:Ray ID="RayControl" runat="server" />

And now in your Ray control, add your button:

<asp:Button ID="ButtonRay" Text="Ray" OnClick="ButtonRay_OnClick" runat="server" />

And in the Ray.ascx.cs code-behind, add your event handler:

protected void ButtonRay_OnClick(object sender, EventArgs e)
{

}

When I add a break-point on this method, run the app, and click the button, the OnClick event is caught like it should be. I think what's happening is that merely referencing your controls doesn't wire up the events. If you were dynamically loading your controls, you have to use Page.LoadControl() so that it wires up correctly.

Let me know if you need more explanation.

EDIT:

I just noticed that your button click method name was not the same as the one your were asking it to call: you have the ButtonRay button doing ButtonRay_Click, but the name of your method is ButtonComment_Click.

Related Topic