进制转换，类型转换

//十六进制字符串转换为十进制

string str = "0c";

int i = int.Parse(str, System.Globalization.NumberStyles.HexNumber); //输出i=12

i = Convert.ToInt32(str, 16); // //输出i=12

//long型到byte[]

public static byte[] getLongToBytes(long s, bool asc) ///ASC=true正常升序输出，false降序输出

{

// long L = 391768031;

byte[] buf = new byte[8];

if (asc)

{

for (int i = 0; i < buf.Length; i++)

{

buf[i] = (byte)(s & 0x00000000000000ff); //和0与去掉高位数据，获取最低位数据

s >>= 8; //右移8位

}

}

else

{

for (int i = buf.Length - 1; i >= 0; i--)

{

buf[i] = (byte)(s & 0x00000000000000ff);

s >>= 8;

}

}

return buf;

}

//byte[]转换为long

public static long getByteToLong(byte[] buf, bool asc)

{

if (buf == null)

{

throw new Exception("byte array is null!");

}

if (buf.Length > 8)

{

throw new Exception("byte array size > 8 !");

}

long r = 0;

if (asc)

{

for (int i = 0; i < buf.Length; i++)

{

r <<= 8;

r |= buf[i] & (long)(0x00000000000000ff);

// r |= Convert.ToInt64((buf[i] & 0x00000000000000ff));

}

}

else

for (int i = buf.Length - 1; i >= 0; i--)

{

r <<= 8;

r |= buf[i] & (long)(0x00000000000000ff);

}

return r;

}

/// <summary>

/// 十六进制字符串转化为List<byte>

/// </summary>

/// <param name="str"></param>

/// <returns></returns>

public List<byte> HexStringTobytes(string str)

{

List<byte> lst = new List<byte>();

string TmpStr = str.ToUpper().Replace("0X", "");

try

{

for (int i = 0; i < TmpStr.Length; i += 2)

{

int iStr = Convert.ToInt32(TmpStr.Substring(i, 2), 16);

lst.Add((byte)iStr);

}

// byte[] b = lst.ToArray(); //List<byte>转换为byte[]

}

catch (Exception e)

{

lst = null;

}

return lst;

}

.