如何转换以下内容?

2934(整数)到B76(十六进制)

让我解释一下我要做什么。我的数据库中有以整数形式存储的用户id。而不是让用户引用他们的id,我想让他们使用十六进制值。主要原因是它比较短。

所以我不仅需要从整数变成十六进制还需要从十六进制变成整数。

在c#中有简单的方法来做到这一点吗?


当前回答

在我找到这个答案之前,我创建了自己的解决方案,将int转换为十六进制字符串并返回。毫不奇怪,它比.net解决方案快得多,因为代码开销更少。

        /// <summary>
        /// Convert an integer to a string of hexidecimal numbers.
        /// </summary>
        /// <param name="n">The int to convert to Hex representation</param>
        /// <param name="len">number of digits in the hex string. Pads with leading zeros.</param>
        /// <returns></returns>
        private static String IntToHexString(int n, int len)
        {
            char[] ch = new char[len--];
            for (int i = len; i >= 0; i--)
            {
                ch[len - i] = ByteToHexChar((byte)((uint)(n >> 4 * i) & 15));
            }
            return new String(ch);
        }

        /// <summary>
        /// Convert a byte to a hexidecimal char
        /// </summary>
        /// <param name="b"></param>
        /// <returns></returns>
        private static char ByteToHexChar(byte b)
        {
            if (b < 0 || b > 15)
                throw new Exception("IntToHexChar: input out of range for Hex value");
            return b < 10 ? (char)(b + 48) : (char)(b + 55);
        }

        /// <summary>
        /// Convert a hexidecimal string to an base 10 integer
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        private static int HexStringToInt(String str)
        {
            int value = 0;
            for (int i = 0; i < str.Length; i++)
            {
                value += HexCharToInt(str[i]) << ((str.Length - 1 - i) * 4);
            }
            return value;
        }

        /// <summary>
        /// Convert a hex char to it an integer.
        /// </summary>
        /// <param name="ch"></param>
        /// <returns></returns>
        private static int HexCharToInt(char ch)
        {
            if (ch < 48 || (ch > 57 && ch < 65) || ch > 70)
                throw new Exception("HexCharToInt: input out of range for Hex value");
            return (ch < 58) ? ch - 48 : ch - 55;
        }

计时代码:

static void Main(string[] args)
        {
            int num = 3500;
            long start = System.Diagnostics.Stopwatch.GetTimestamp();
            for (int i = 0; i < 2000000; i++)
                if (num != HexStringToInt(IntToHexString(num, 3)))
                    Console.WriteLine(num + " = " + HexStringToInt(IntToHexString(num, 3)));
            long end = System.Diagnostics.Stopwatch.GetTimestamp();
            Console.WriteLine(((double)end - (double)start)/(double)System.Diagnostics.Stopwatch.Frequency);

            for (int i = 0; i < 2000000; i++)
                if (num != Convert.ToInt32(num.ToString("X3"), 16))
                    Console.WriteLine(i);
            end = System.Diagnostics.Stopwatch.GetTimestamp();
            Console.WriteLine(((double)end - (double)start)/(double)System.Diagnostics.Stopwatch.Frequency);
            Console.ReadLine(); 
        }

结果:

Digits : MyCode : .Net
1 : 0.21 : 0.45
2 : 0.31 : 0.56
4 : 0.51 : 0.78
6 : 0.70 : 1.02
8 : 0.90 : 1.25

其他回答

整数到十六进制:

Int a = 72; 控制台。WriteLine(“{0:X}”);

十六进制到整型:

int b = 0xB76; Console.WriteLine (b);

在我找到这个答案之前,我创建了自己的解决方案,将int转换为十六进制字符串并返回。毫不奇怪,它比.net解决方案快得多,因为代码开销更少。

        /// <summary>
        /// Convert an integer to a string of hexidecimal numbers.
        /// </summary>
        /// <param name="n">The int to convert to Hex representation</param>
        /// <param name="len">number of digits in the hex string. Pads with leading zeros.</param>
        /// <returns></returns>
        private static String IntToHexString(int n, int len)
        {
            char[] ch = new char[len--];
            for (int i = len; i >= 0; i--)
            {
                ch[len - i] = ByteToHexChar((byte)((uint)(n >> 4 * i) & 15));
            }
            return new String(ch);
        }

        /// <summary>
        /// Convert a byte to a hexidecimal char
        /// </summary>
        /// <param name="b"></param>
        /// <returns></returns>
        private static char ByteToHexChar(byte b)
        {
            if (b < 0 || b > 15)
                throw new Exception("IntToHexChar: input out of range for Hex value");
            return b < 10 ? (char)(b + 48) : (char)(b + 55);
        }

        /// <summary>
        /// Convert a hexidecimal string to an base 10 integer
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        private static int HexStringToInt(String str)
        {
            int value = 0;
            for (int i = 0; i < str.Length; i++)
            {
                value += HexCharToInt(str[i]) << ((str.Length - 1 - i) * 4);
            }
            return value;
        }

        /// <summary>
        /// Convert a hex char to it an integer.
        /// </summary>
        /// <param name="ch"></param>
        /// <returns></returns>
        private static int HexCharToInt(char ch)
        {
            if (ch < 48 || (ch > 57 && ch < 65) || ch > 70)
                throw new Exception("HexCharToInt: input out of range for Hex value");
            return (ch < 58) ? ch - 48 : ch - 55;
        }

计时代码:

static void Main(string[] args)
        {
            int num = 3500;
            long start = System.Diagnostics.Stopwatch.GetTimestamp();
            for (int i = 0; i < 2000000; i++)
                if (num != HexStringToInt(IntToHexString(num, 3)))
                    Console.WriteLine(num + " = " + HexStringToInt(IntToHexString(num, 3)));
            long end = System.Diagnostics.Stopwatch.GetTimestamp();
            Console.WriteLine(((double)end - (double)start)/(double)System.Diagnostics.Stopwatch.Frequency);

            for (int i = 0; i < 2000000; i++)
                if (num != Convert.ToInt32(num.ToString("X3"), 16))
                    Console.WriteLine(i);
            end = System.Diagnostics.Stopwatch.GetTimestamp();
            Console.WriteLine(((double)end - (double)start)/(double)System.Diagnostics.Stopwatch.Frequency);
            Console.ReadLine(); 
        }

结果:

Digits : MyCode : .Net
1 : 0.21 : 0.45
2 : 0.31 : 0.56
4 : 0.51 : 0.78
6 : 0.70 : 1.02
8 : 0.90 : 1.25

微软网络框架

非常好的解释和少数编程行 好工作

// Store integer 182
int intValue = 182;
// Convert integer 182 as a hex in a string variable
string hexValue = intValue.ToString("X");
// Convert the hex string back to the number
int intAgain = int.Parse(hexValue, System.Globalization.NumberStyles.HexNumber);

PASCAL >> c#

http://files.hddguru.com/download/Software/Seagate/St_mem.pas

从老式的pascal转换成c#的程序

    /// <summary>
    /// Conver number from Decadic to Hexadecimal
    /// </summary>
    /// <param name="w"></param>
    /// <returns></returns>
    public string MakeHex(int w)
    {
        try
        {
           char[] b =  {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
           char[] S = new char[7];

              S[0] = b[(w >> 24) & 15];
              S[1] = b[(w >> 20) & 15];
              S[2] = b[(w >> 16) & 15];
              S[3] = b[(w >> 12) & 15];
              S[4] = b[(w >> 8) & 15];
              S[5] = b[(w >> 4) & 15];
              S[6] = b[w & 15];

              string _MakeHex = new string(S, 0, S.Count());

              return _MakeHex;
        }
        catch (Exception ex)
        {

            throw;
        }
    }
int valInt = 12;
Console.WriteLine(valInt.ToString("X"));  // C  ~ possibly single-digit output 
Console.WriteLine(valInt.ToString("X2")); // 0C ~ always double-digit output

十六进制:

string hex = intValue.ToString("X");

整数:

int intValue = int.Parse(hex, System.Globalization.NumberStyles.HexNumber)