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c# - Set an empty DateTime variable

I would declare an empty String variable like this:

    string myString = string.Empty;

Is there an equivalent for a 'DateTime' variable ?

Update :

The problem is I use this 'DateTime' as a parameter for a 'StoredProcedure' in SQL. E.g:

    DateTime? someDate = null;
    myCommand.Parameters.AddWithValue("@SurgeryDate", someDate);

When I run this code an exception is catched telling me the 'StoredProcedure' expected a '@SurgeryDate' parameter. But i provided it. Any idea why?

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Since DateTime is a value type you cannot assign null to it, but exactly for these cases (absence of a value) Nullable<T> was introduced - use a nullable DateTime instead:

DateTime? myTime = null;

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