Adding a persistable TextBox property

[Jason Barnett]

I've developed a control that inherits from TextBox. I created a property
that gets rendered into a HiddenField, which is altered by javascript at run
time. The HiddenField is initialized during OnInt, and added to the controls
collection during CreateChildControls. Also, I've overridden the
LoadPostData method to retrieve the property value based on the HiddenField's
ID.

All works well, but I'm concerned about the last step (retrieving the value
during LoadPostData). I'm curious if there is a way to get ASP.NET will
restore the ViewState of the child control for me. Is anyone aware of a
better way to handle this?