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Comparisons with boxed value types

If value types are assigned to variables of type object they are boxed - the value is stored in an
instance of a System.Object. This can lead to unintended consequences when comparing values
with ==, e.g.:

object left = (int)1; // int in an object box
object right = (int)1; // int in an object box

var comparison1 = left == right; // false

This can be avoided by using the overloaded Equals method, which will give the expected result.

var comparison2 = left.Equals(right); // true

Alternatively, the same could be done by unboxing the left and right variables so that the int
values are compared:

var comparison3 = (int)left == (int)right; // true

Conversion of boxed value types

Boxed value types can only be unboxed into their original Type, even if a conversion of the two Type
s is valid, e.g.:

object boxedInt = (int)1; // int boxed in an object

long unboxedInt1 = (long)boxedInt; // invalid cast

This can be avoided by first unboxing into the original Type, e.g.:

long unboxedInt2 = (long)(int)boxedInt; // valid

Read Built-in Types online: https://riptutorial.com/csharp/topic/42/built-in-types

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