Gets or sets the value of the bit at a specific position in the BitArray in C#

The BitArray class in C# provides an indexer that allows you to get or set the value of a bit at a specific position. You can access individual bits using either the indexer syntax arr[index] or the Get() and Set() methods.

Syntax

Following is the syntax for accessing bits in a BitArray −

// Using indexer to get/set bits
bitArray[index] = true;  // Set bit at index
bool value = bitArray[index];  // Get bit at index

// Using Get() and Set() methods
bool value = bitArray.Get(index);  // Get bit at index
bitArray.Set(index, true);  // Set bit at index

Parameters

• index ? The zero-based index of the bit to access.

• value ? The boolean value to set (true or false).

Using Indexer to Get and Set Bits

The indexer provides the most direct way to access individual bits in a BitArray −

using System;
using System.Collections;

public class Demo {
   public static void Main() {
      BitArray arr1 = new BitArray(4);
      
      // Set bits using indexer
      arr1[0] = false;
      arr1[1] = true;
      arr1[2] = false;
      arr1[3] = true;
      
      Console.WriteLine("BitArray length = " + arr1.Length);
      Console.WriteLine("Bit at index 0: " + arr1[0]);
      Console.WriteLine("Bit at index 1: " + arr1[1]);
      Console.WriteLine("Bit at index 2: " + arr1[2]);
      Console.WriteLine("Bit at index 3: " + arr1[3]);
      
      // Update a bit value
      Console.WriteLine("\nUpdating bit at index 0 to true...");
      arr1[0] = true;
      Console.WriteLine("Bit at index 0 [UPDATED]: " + arr1[0]);
   }
}

The output of the above code is −

BitArray length = 4
Bit at index 0: False
Bit at index 1: True
Bit at index 2: False
Bit at index 3: True

Updating bit at index 0 to true...
Bit at index 0 [UPDATED]: True

Using Get() and Set() Methods

You can also use the Get() and Set() methods to access individual bits −

using System;
using System.Collections;

public class Demo {
   public static void Main() {
      BitArray arr = new BitArray(3);
      
      // Set bits using Set() method
      arr.Set(0, false);
      arr.Set(1, true);
      arr.Set(2, false);
      
      Console.WriteLine("BitArray elements using Get() method:");
      for (int i = 0; i < arr.Length; i++) {
         Console.WriteLine("Bit at index " + i + ": " + arr.Get(i));
      }
      
      // Update using Set() method
      Console.WriteLine("\nUpdating bit at index 2 to true...");
      arr.Set(2, true);
      Console.WriteLine("Bit at index 2 [UPDATED]: " + arr.Get(2));
      
      // Display all elements
      Console.WriteLine("\nAll elements:");
      foreach (bool bit in arr) {
         Console.WriteLine(bit);
      }
   }
}

The output of the above code is −

BitArray elements using Get() method:
Bit at index 0: False
Bit at index 1: True
Bit at index 2: False

Updating bit at index 2 to true...
Bit at index 2 [UPDATED]: True

All elements:
False
True
True

Comparison of Access Methods

Conclusion

The BitArray class provides flexible ways to access individual bits through both indexer syntax and explicit methods. The indexer approach arr[index] is more concise and commonly used, while the Get() and Set() methods offer explicit control over bit manipulation operations.