C# | Get or set the number of elements in the BitArray

The BitArray class manages a compact array of bit values, which are represented as Booleans, where true indicates that the bit is on i.e, 1 and false indicates the bit is off i.e, 0. This class is contained in System.Collections namespace.
BitArray.Length property is used to get or set the number of elements in the BitArray.

Properties:

• The BitArray class is a collection class in which the capacity is always the same as the count.
• Elements are added to a BitArray by increasing the Length property.
• Elements are deleted by decreasing the Length property.
• Elements in this collection can be accessed using an integer index. Indexes in this collection are zero-based.

Syntax:

public int Length { get; set; }

Return Value: The number of elements in the BitArray.

Exception: This method will give ArgumentOutOfRangeException if the property is set to a value which is less than zero.

Below programs illustrate the use of BitArray.Length Property:

Example 1:

// C# code to get or set the
// number of elements in the BitArray
using System;
using System.Collections;

class GFG {

    // Driver code
    public static void Main()
    {

        // Creating a BitArray myBitArr
        BitArray myBitArr = new BitArray(new byte[] { 0, 0, 0, 1 });

        // Displaying the number of
        // elements in myBitArr
        Console.WriteLine(myBitArr.Length);
    }
}

Output:

32

Example 2:

// C# code to get or set the
// number of elements in the BitArray
using System;
using System.Collections;

class GFG {

    // Driver code
    public static void Main()
    {

        // Creating a BitArray myBitArr
        BitArray myBitArr = new BitArray(new byte[] {});

        // Displaying the number of
        // elements in myBitArr
        Console.WriteLine(myBitArr.Length);
    }
}

Output:

0

Note:

• Length and Count return the same value. Length can be set to a specific value, but Count is read-only.
• If Length is set to a value that is less than Count, the BitArray is truncated and the elements after the index value -1 are deleted.
• If Length is set to a value that is greater than Count, the new elements are set to false.
• Retrieving the value of this property is an O(1) operation. Setting this property is an O(n) operation.

Reference:

• https://docs.microsoft.com/en-us/dotnet/api/system.collections.bitarray.length?view=netframework-4.7.2