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// Define some local nullable types using Nullable.

Nullable nullableInt = 10;

Nullable nullableDouble = 3.14;

Nullable nullableBool = null;

Nullable nullableChar = 'a';

Nullable[] arrayOfNullableInts = new int?[10];

}

Working with Nullable Types

As stated, nullable data types can be particularly useful when you are interacting with databases,

given that columns in a data table may be intentionally empty (e.g., undefined). To illustrate,

assume the following class, which simulates the process of accessing a database that has a table

containing two columns that may be null. Note that the GetIntFromDatabase() method is not

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assigning a value to the nullable integer member variable, while GetBoolFromDatabase() is assigning

a valid value to the bool? member:

class DatabaseReader

{