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So, how can we check if two different
map location objects represent the same

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location on the map?

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If we go to the documentation for

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system.object we'll find
a method named Equals.

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This is the method that is called
to determine if two objects

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are practically equal.

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By default, it just calls
the ReferenceEquals method to see if two

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objects refer to the same object but
we can override this behavior.

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Let's do that in the point class and map
location will inherit this new behavior.

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So we can overwrite equals to return true

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if the coordinates of
the two points are equal.

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So we'll say public override.

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Equals and
equals takes a parameter of type Object.

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We can type system.object or
we can just type object.

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System.object is the actual
name of the object class.

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Object with the lowercase o is
just an alias just like int

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actually refers to System.int32.

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We'll call our parameter obj.

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The first thing we need to do is to
make sure that the object passed in

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is in fact of type point.

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So we can say if(!(obj is Point))

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then, Will return false.

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Because if the object passed in,
isn't a point,

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they can't possibly equal each other,
now can they?

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Using the is operator also has the nice
effect of checking to make sure

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that it isn't null either.

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Because if obj is null, then this
obj is point will also return false.

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Now that we know that they are the same
type, we need to cast obj to a point.

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We'll call it that.

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Now we can return true if this .X.

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Equals that .X.

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And this .Y.

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equals.

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That .Y.

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Now let's go back to
the Is.OnPath method and

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change this from using the equality
operator to using .Equals.

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We do this because we don't want to check
if the objects are the exact same object.

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We just want to check to see if they
are same for all intents and purposes.

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That is, they refer to the same
coordinates on the map.

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Unless we really want to check if two
variables refer to the exact same object,

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we should always use equals
instead of the equality operator.

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The caveat to this rule is when dealing
with numeric types and strings.

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In the case of strings and
numeric types like int and double.

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The equality operator
will always return true

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if the objects contain the same value.

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So when dealing with strings,
ints, and doubles.

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We can always use the equality operator.

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And it will have the same
result as if we called equals.

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Let's compile and run our program to see
if the Is.OnPath method works as expected.

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Now.

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Yay!
We get our message printed out so

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it works as expected, but
what does this compiler warning here?

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This is telling us that if
we override object.equals

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we should also override
object.GetHashCode.

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We'll learn about the GetHashCode
method in the next video.