Question

I was doing some type conversion routines last night for a system I am working on. One of the conversions involves turning string values into their DateTime equivalents.

While doing this, I noticed that the Convert.ToDateTime() method had an overload which accepted a boolean parameter.

First question? Under what circumstances could this ever be useful?

I went a little further and tried to execute the method in QuickWatch. Either way ( true or false ), the routine returns an InvalidCastException.

Second question? Why is this method even here?

EDIT

Thanks for the answers, guys. I can see how it makes sense from a contractual point of view, but it does seem odd that the core framework includes methods that:-

• Can never work
• Worse, will actually throw an exception when someone tries to call it.

It’s a bit like someone making a car loaded with controls that actively stop your vehicle from working when used.

Answer 1

It makes sense because ToDateTime is part of the IConvertible interface implemented by bool. If you look in reflector you will see that it throws an InvalidCastException.

Update (from Convert):

public static DateTime ToDateTime(bool value)
{
    return ((IConvertible) value).ToDateTime(null);
}