C#中各種字元類型的轉化

            //字元長度的理解
            string s = "我是一個2兵";
            int len = s.Length;//6個字元   
            byte[] sarr = System.Text.Encoding.Default.GetBytes(s);
            len = sarr.Length;//11個位元組   
            
            //10進位轉字串，也沒有意義，要轉成對應的ascii碼
            int t1 = 81;
            string s1 = t1.ToString();
            //這個10進位轉對應ASCII字元才有意義。
            s1 = ((char)t1).ToString();

            //16進位轉字串:這個沒有意義。就是tostring了。
            int intAB = 0x16;  
            s1 = intAB.ToString();
            //16進位轉對應ASCII字元:
            byte babb = 0x45;
            string ass = ((char)babb).ToString();

            //ASCII字串轉10進位數
            string tr = "2Ab劉";
            string d ="";
            for (int i = 0; i < tr.Length; i++)
            {
                int ii = (int)Convert.ToChar(tr.Substring(i, 1));
                d = d +" "+ ii.ToString();
            }
            //ASCII字串轉16進位數
            string s2 = "2Ab劉";
            byte[] ba = System.Text.ASCIIEncoding.Default.GetBytes(s2);
            StringBuilder sb = new StringBuilder();
            foreach (byte b in ba)
            {
                sb.Append(b.ToString("x") + " ");
            }
            //16進位數轉10進位
            int intA = 0x16;//定義的時候是必須帶0x的   
            string strA = "16";//字串可以不帶   
            int intA1 = Convert.ToInt32(intA);
            int intA2 = Convert.ToInt32(strA, 16);

            //10進位轉16進位
            strA = Convert.ToString(intA2, 16);

            //10進位轉2進位，16進位類似
            int int10 = 10;
            string str2 = Convert.ToString(int10,2);

            //2進位轉10進位
            int10 = Convert.ToInt32(str2,2);