C# 0 The Complete Reference

PART I

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PART IPART I

class FailSoftArray {

  int[] a; // reference to underlying array

  // Construct array given its size.

  public FailSoftArray(int size) {

    a = new int[size];

    Length = size;

  }

  // An auto-implemented, read-only Length property.

  public int Length { get; private set; }

  // An auto-implemented, read-only Error property.

  public bool Error { get; private set; }

  // This is the indexer for FailSoftArray.

  public int this[int index] {

    // This is the get accessor.

    get {

      if(ok(index)) {

        Error = false;

        return a[index];

      } else {

        Error = true;

        return 0;

      }

    }

    // This is the set accessor.

    set {

      if(ok(index)) {

        a[index] = value;

        Error = false;

      }

      else Error = true;

    }

  }

  // Return true if index is within bounds.

  private bool ok(int index) {

   if(index >= 0 & index < Length) return true;

   return false;

  }

}

// Demonstrate the improved fail-soft array.

class FinalFSDemo {

  static void Main() {

    FailSoftArray fs = new FailSoftArray(5);

    // Use Error property.

    for(int i=0; i < fs.Length + 1; i++) {

      fs[i] = i*10;

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      if(fs.Error)

        Console.WriteLine("Error with index " + i);

    }

  }

}

This version of 

FailSoftArray

 works the same as the previous version, but it does not 

contain the explicitly declared backing fields.

Here are some restrictions that apply to using access modifiers with accessors. First, 

only the