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Start your free trialbabasariffodeen
6,475 PointsI do not understand the : base part. What is it doing?
I really do not understand what happens when you've created the Square base class (derived from Polygon) and then thereafter you state parameter but followed by : and the word 'base'.
Please can someone explain this to me using examples other than squares/polygons?
Thank you
namespace Treehouse.CodeChallenges
{
class Polygon
{
public readonly int NumSides;
public Polygon(int numSides)
{
NumSides = numSides;
}
}
}
1 Answer
Steven Parker
231,198 Pointsbase refers to the parent class that the current one inherits from.
A derived class constructor always calls its parent class constructor first. Typically, there is no special syntax and the parent's default constructor is used.
In cases where the parent has no default constructor, or where an alternative constructor is desired, the ": base()
" syntax can be used to specify the argument(s) to be passed to the alternative parent constructor.
babasariffodeen
6,475 Pointsbabasariffodeen
6,475 PointsThanks :)
Would it be possible to perhaps give an example of a child class calling a base class constructor? But something other than Square/Polygon. It would be helpful for me to see it used in another way. Something simple.
Thank you