I run into this infrequently enough that I have to search on the properties. Since I usually have a hard time finding the details...
Using the "Bindable" attribute on a public property will make this property available through the design-time properties and settable on the aspx.
The aspx setting for the following property would be:
<csc:ExpandoList
ID="List-O-Stuff"
CssClass="expandoList"
UnhideableRowCount=7 />
[Bindable(true),
Category("Appearance"),
DefaultValue(5)]
public int
UnhideableRowCount
{
get
{
return
_unhideableRowCount;
}
set
{
_unhideableRowCount = value;
}
}