Custom Control with a complex property type

[Jeremy Chapman]

I have a property will an array of webcontrols.

The control features a custom property editor which can add and remove web
controls to the array, but how do I persist the informtion by serializing it
to the aspx page?

For example, right now, here is what the html looks like when I drag my
control on to the page and add some web controls to the ControlList
property:

<myasp:MyControl id="MyControl6" runat="server" Height="32px" Width="152px"
ControlList="WebControl[] Array"></myasp:MyControl>

What I want is for the ControlList property to serialize something like:

<myasp:MyControl id="MyControl6" runat="server" Height="32px" Width="152px">
<ControlList>
<asp:linkbutton id="LinkButton1"
runat="server">LinkButton</asp:linkbutton>
<asp:imagebutton id="ImageButton1" runat="server"></asp:imagebutton>
<asp:button id="Button1" runat="server" Text="Button"></asp:button>
<asp:hyperlink id="HyperLink1"
runat="server">HyperLink</asp:hyperlink>
<asp:label id="Label1" runat="server">Label</asp:label>
</ControlList>
</myasp:MyControl>

Is this possible?

 

[Jeremy Chapman]

I've solved the first issue by adding the following attribute to my custom
property:

[DesignerSerializationVisibility(DesignerSerializationVisibility.Content),
NotifyParentProperty(true),
PersistenceMode(PersistenceMode.InnerProperty)]

This causes the html in my aspx page to look like:

<myasp:MyControl id="MyControl1" runat="server" Width="88px" Height="266px">
<ControlList>
<asp:Button ID="frmControlButton0"></asp:Button>
</ControlList>
</myasp:MyControl>

But now, if I close my web form and re-open it, Visual studio can't create
the control on my page, I get an error '' could not be set on property
ControlList. What does this mean?

Here is the relevant code to my control:

[DefaultProperty("ControlList"),
ToolboxData("<{0}:MyControl runat=server></{0}:MyControl>")]
public class MyControl : System.Web.UI.WebControls.WebControl
{
private System.Web.UI.WebControls.WebControl[] pControls_m = null;

[Category("Appearance"),DefaultValue(""),
Editor(typeof(ControlListEditor),
typeof(System.Drawing.Design.UITypeEditor))]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content),
NotifyParentProperty(true),
PersistenceMode(PersistenceMode.InnerProperty)]
public System.Web.UI.WebControls.WebControl[] ControlList
{
get
{
return pControls_m;
}
set
{
pControls_m = value;
}
}
}