位数组的实现.txt

来自「C# 是创新性的新式编程语言」· 文本 代码 · 共 50 行

using System;
namespace Movecont
{
		public class BitArray
		{
			private Byte[]byteArray;
			private Int32 numBits;
			public BitArray(Int32 numBits)
			{
				if(numBits<=0)
					throw new ArgumentOutOfRangeException("numBits","numBits must be>0");
				this.numBits=numBits;
				byteArray=new Byte[(numBits+7)/8];
			}
			public Boolean this[Int32 bitPos]
			{
				get
				{
					if((bitPos<0)||(bitPos>=numBits))
						throw new IndexOutOfRangeException();
					return (byteArray[bitPos/8]&(1<<(bitPos%8)))!=0;
				}
				set
				{
					if((bitPos<0)||(bitPos>=numBits))
						throw new IndexOutOfRangeException();
					if(value)
					{
						byteArray[bitPos/8]=(Byte)(byteArray[bitPos/8]|(1<<(bitPos%8)));
					}
					else
					{
						byteArray[bitPos/8]=(Byte)(byteArray[bitPos/8]&~(1<<(bitPos%8)));
					}
					
			}
		}
	}
	class App
	{
		static void Main()
		{
			BitArray ba=new BitArray(14);
			for(Int32 x=0;x<14;x++)
				ba[x]=(x%2==0);
			for(Int32 x=0;x<14;x++)
				Console.WriteLine("Bit "+x+" is "+(ba[x]?"On":"Off"));	
		}	
	}
}