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C# Intermediate C# Polymorphism Accessor Access Modifiers

Posted by shawn khah
shawn khah
15,082 Points

help plz

Challenge Task 1 of 1

SequenceDetector now has a LastScannedSequence property. Change the access of the LastScannedSequence property so that only SequenceDetector and its subclasses can set the LastScannedSequence property. Other classes should still be able to get the last scanned sequence. Important: In each task of this code challenge, the code you write should be added to the code from the previous task. Restart Preview Get Help Check Work SequenceDetector.cs RepeatDetector.cs

1 namespace Treehouse.CodeChallenges 2 { 3 class SequenceDetector 4 { 5 public virtual string Description => ""; 6 ā€‹ 7 public int[] LastScannedSequence { get; private set; } 8 ā€‹ 9 public virtual bool Scan(int[] sequence) 10 { 11 LastScannedSequence = sequence; 12 return true; 13 } 14 } 15 } 16 ā€‹

SequenceDetector.cs 
namespace Treehouse.CodeChallenges
{
    class SequenceDetector
    {
        public virtual string Description => "";

        public int[] LastScannedSequence { get; private set; }

        public virtual bool Scan(int[] sequence)
        {
            LastScannedSequence = sequence;
            return true;
        }
    }
}
RepeatDetector.cs 
namespace Treehouse.CodeChallenges
{
    class RepeatDetector : SequenceDetector
    {
        public override string Description => "Detects repetitions";

        public override bool Scan(int[] sequence)
        {
            LastScannedSequence = sequence;

            if(sequence.Length < 2)
            {
                return false;
            }

            for(int i = 1; i < sequence.Length; ++i)
            {
                if(sequence[i] == sequence[i-1])
                {
                    return true;
                }
            }

            return false;
        }
    }
}

1 Answer

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

The term you're looking for is "protected".

When "private", only the class itself can set the property. But "protected" allows the class and its subclasses to set the property.