//1.请问c#中如何将十进制数的字符串转化成十六进制数的字符串

//十进制转二进制
Console.WriteLine("十进制166的二进制表示: "+Convert.ToString(166, 2));
//十进制转八进制
Console.WriteLine("十进制166的八进制表示: "+Convert.ToString(166, 8));
//十进制转十六进制
Console.WriteLine("十进制166的十六进制表示: "+Convert.ToString(166, 16));
    
//二进制转十进制
Console.WriteLine("二进制 111101 的十进制表示: "+Convert.ToInt32("111101", 2));
//八进制转十进制
Console.WriteLine("八进制 44 的十进制表示: "+Convert.ToInt32("44", 8));
//十六进制转十进制
Console.WriteLine("十六进制 CC的十进制表示: "+Convert.ToInt32("CC", 16));

//2.在串口通讯过程中,经常要用到 16进制与字符串、字节数组之间的转换
private string StringToHexString(string s,Encoding encode)
{
	byte[] b = encode.GetBytes(s);//按照指定编码将string编程字节数组
	string result = string.Empty;
	for (int i = 0; i < b.Length; i++)//逐字节变为16进制字符,以%隔开
	{
		result += "%"+Convert.ToString(b[i], 16);
	}
	return result;
}
private string HexStringToString(string hs, Encoding encode)
{
	//以%分割字符串,并去掉空字符
	string[] chars = hs.Split(new char[]{'%'},StringSplitOptions.RemoveEmptyEntries);
	byte[] b = new byte[chars.Length];
	//逐个字符变为16进制字节数据
	for (int i = 0; i < chars.Length; i++)
	{
		b[i] = Convert.ToByte(chars[i], 16);
	}
	//按照指定编码将字节数组变为字符串
	return encode.GetString(b);
}

/// <summary>
/// 字符串转16进制字节数组
/// </summary>
/// <param name="hexString"></param>
/// <returns></returns>
private static byte[] strToToHexByte(string hexString)
{
	 hexString = hexString.Replace(" ", "");
   if ((hexString.Length % 2) != 0)
		 hexString += " ";
	byte[] returnBytes = new byte[hexString.Length / 2];
	for (int i = 0; i < returnBytes.Length; i++)
		returnBytes[i] = Convert.ToByte(hexString.Substring(i * 2, 2), 16);
	return returnBytes;
 }

/// <summary>
/// 字节数组转16进制字符串
/// </summary>
/// <param name="bytes"></param>
/// <returns></returns>
public static string byteToHexStr(byte[] bytes)
{
	string returnStr = "";
	if (bytes != null)
	{
		for (int i = 0; i < bytes.Length; i++)
		{
			 returnStr += bytes[i].ToString("X2");
		 }
	 }
	return returnStr;
 }

/// <summary>
/// 从汉字转换到16进制
/// </summary>
/// <param name="s"></param>
/// <param name="charset">编码,如"utf-8","gb2312"</param>
/// <param name="fenge">是否每字符用逗号分隔</param>
/// <returns></returns>
public static string ToHex(string s, string charset, bool fenge)
{
	if ((s.Length % 2) != 0)
	{
		 s += " ";//空格
		//throw new ArgumentException("s is not valid chinese string!");
	 }
	 System.Text.Encoding chs = System.Text.Encoding.GetEncoding(charset);
	byte[] bytes = chs.GetBytes(s);
	string str = "";
	for (int i = 0; i < bytes.Length; i++)
	{
		str += string.Format("{0:X}", bytes[i]);
		if (fenge && (i != bytes.Length - 1))
		{
			 str += string.Format("{0}", ",");
		 }
	 }
	return str.ToLower();
 }


///<summary>
/// 从16进制转换成汉字
/// </summary>
/// <param name="hex"></param>
/// <param name="charset">编码,如"utf-8","gb2312"</param>
/// <returns></returns>
public static string UnHex(string hex, string charset)
{
   if (hex == null)
		throw new ArgumentNullException("hex");
	 hex = hex.Replace(",", "");
	 hex = hex.Replace("\n", "");
	 hex = hex.Replace("\\", "");
	 hex = hex.Replace(" ", "");
	if (hex.Length % 2 != 0)
	{
		 hex += "20";//空格
	 }
	// 需要将 hex 转换成 byte 数组。 
	byte[] bytes = new byte[hex.Length / 2];

   for (int i = 0; i < bytes.Length; i++)
	{
		try
		{
			// 每两个字符是一个 byte。 
			 bytes[i] = byte.Parse(hex.Substring(i * 2, 2),
			 System.Globalization.NumberStyles.HexNumber);
		 }
		catch
		{
			// Rethrow an exception with custom message. 
			throw new ArgumentException("hex is not a valid hex number!", "hex");
		 }
	 }
	 System.Text.Encoding chs = System.Text.Encoding.GetEncoding(charset);
	return chs.GetString(bytes);
 }


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