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C# C# Objects Inheritance Throwing Exceptions

Posted by Ted Pennington
Ted Pennington
1,271 Points

Multiple arguments handed to OnMap?

When map.OnMap(this) is called, and the object being created is passed (this), OnMap is expecting two arguments (x and y). But our MapLocation object is constructed with three arguments (x, y, and map). How does the OnMap method know to use the x and y values? Is it because they are the first two arguments passed? What would happen if we changed the order of the parameters?

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The OnMap method can take a single argument of type "Point". Since a "MapLocation" inherits from "Point", it is valid to pass it (this) as the argument.

The x and y values are contained inside the object.