Wierd stuff about properties in User Control

I have few properties in my User Conrol. Some of them are simple type and some have type of my class, like this:

public FromTo Interval
    {
        get { return interval; }
        set { interval = value; }
    }

    public short From
    {
        get { return from; }
        set { from = value; }
    }
I set prorerties declaratively. The strange stuff for me is that properties of my types (like FromTo) are passed to user control only after DataBind() for control is called...


Why is it like this?

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