【急】二进制有关问题

【急急急】二进制问题
如何把一个十进制转化成二进制。
然后把二进制指定的位置 进行置0或者置1

[解决办法]

C# code

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;namespace JinZhiTest{    public partial class Form1 : Form    {        private int CurrBase = 10;//当前进制，开始默认为10        public Form1()        {            InitializeComponent();        }        //转换成二进制        private void rdoEr_Click(object sender, EventArgs e)        {            this.JinZhiZhuHuan(CurrBase, 2);        }        //转换成八进制        private void rdoBa_Click(object sender, EventArgs e)        {            this.JinZhiZhuHuan(CurrBase, 8);        }        //转换成十进制        private void rdoShi_Click(object sender, EventArgs e)        {            this.JinZhiZhuHuan(CurrBase, 10);        }        //转换成十六进制        private void rdoShiLiu_Click(object sender, EventArgs e)        {            this.JinZhiZhuHuan(CurrBase, 16);        }        /// <summary>        /// 进制转换        /// </summary>        /// <param name="fromBase">原进制</param>        /// <param name="toBase">目标进制</param>        private void JinZhiZhuHuan(int fromBase, int toBase)        {            //得到文本框中数的十进制            int num = Convert.ToInt32(this.textBox1.Text.Trim(), fromBase);            //将数转换成目标进制的字符串形式并显示在文本框中            this.textBox1.Text = Convert.ToString(num, toBase);            //将目标进制保存为当前进制            this.CurrBase = toBase;        }
[解决办法]
十进制转换二进制string j = Convert.ToString(i, 2);
至于置0，你可以用Replace函数
[解决办法]
C# code
        int value = 100;        string r = Convert.ToString(value, 2);        Response.Write(r);
[解决办法]
int x = 100; // 64(16) 1100100
如果想置第2位为1，则
x |= 0x0000010;
置0，则
x &= 0x1111011;
[解决办法]
C# code
using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;namespace JinZhiTest{    public partial class Form1 : Form    {        private int CurrBase = 10;//当前进制，开始默认为10        public Form1()        {            InitializeComponent();        }        //转换成二进制        private void rdoEr_Click(object sender, EventArgs e)        {            this.JinZhiZhuHuan(CurrBase, 2);        }        //转换成八进制        private void rdoBa_Click(object sender, EventArgs e)        {            this.JinZhiZhuHuan(CurrBase, 8);        }        //转换成十进制        private void rdoShi_Click(object sender, EventArgs e)        {            this.JinZhiZhuHuan(CurrBase, 10);        }        //转换成十六进制        private void rdoShiLiu_Click(object sender, EventArgs e)        {            this.JinZhiZhuHuan(CurrBase, 16);        }        /// <summary>        /// 进制转换        /// </summary>        /// <param name="fromBase">原进制</param>        /// <param name="toBase">目标进制</param>        private void JinZhiZhuHuan(int fromBase, int toBase)        {            //得到文本框中数的十进制            int num = Convert.ToInt32(this.textBox1.Text.Trim(), fromBase);            //将数转换成目标进制的字符串形式并显示在文本框中            this.textBox1.Text = Convert.ToString(num, toBase);            //将目标进制保存为当前进制            this.CurrBase = toBase;        }    }}
[解决办法]
可以用扩展方法，读起来比较自然。
C# code 
 
static class Int32Extension{    public static int SetBit(this int value, int bitIndex)    {        if( bitIndex < 0 || bitIndex > 31) throw new ArgumentOutOfRangeException();        return value | (1 << bitIndex);    }    public static int ClearBit(this int value, int bitIndex)    {        if (bitIndex < 0 || bitIndex > 31) throw new ArgumentOutOfRangeException();        return value & ~(1 << bitIndex);    }}class Program{    static void Main(string[] args)    {        int i = 123;            // i = 1111011        int j = i.ClearBit(0);  // j = 1111010        int k = j.SetBit(0);    // k = 1111011    }}