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C# Intermediate C# Polymorphism Review

Posted by Fabiola Barrientos
Fabiola Barrientos
9,467 Points

Unexpected error

Whenever I run the program I keep on getting the eroor: Level.cs(15,21): error CS0161: `TreehouseDefense.Level.Play()': not all code paths re turn a value

Here is the code the error refers to. Could I get any help? I dont understand my code is exactly as it appears in the video.

public bool Play()
        {
            //Run until all invaders are dead or an invader reaches the end.
            int remainingInvaders = _invaders.Length;

            while(remainingInvaders > 0)
            {
                //Each tower has opportunity to fire on invaders
                foreach(Tower tower in Towers)
                {
                    tower.FireOnInvaders(_invaders);
                }

                //Counr and move iinvaders that are still active.
                remainingInvaders = 0;
                foreach(Invader invader in _invaders)
                {
                    if(invader.IsActive)
                    {
                        invader.Move();

                        if(invader.HasScored)
                        {
                            return false;
                        }

                        remainingInvaders++;
                    }
                }
            }
        }
Fabiola Barrientos
Fabiola Barrientos
9,467 Points

For some reason it wont let me paste the beggining part so ill paste it here

public bool Play() { //Run until all invaders are dead or an invader reaches the end. int remainingInvaders = _invaders.Length;

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

Your paste was OK, you just forgot to use Markdown formatting.

1 Answer

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

Your function is defined to return a bool, which it does when it finds an invader that "HasScored".

But if it does not, it currently doesn't return anything, and that's causing the error.