1、int整形转为byte[]数组：高位存储在前，低位存储在后    

public static byte[] IntToByte(this int source, int fromebase = 4)
{List<byte> buff = new List<byte>();for (int i = fromebase - 1; i >= 0; i--){buff.Add((byte)(source>>(8 * i)));}return buff.ToArray();
}

2、字符串转对应ASCII码，byte[]数组    

    public static byte[] StringToByte(this string source){return Encoding.Default.GetBytes(source);}

3、十六进制字符串数组转为byte[]数组   

    public static byte[] HexStringToByte(this string source){if (string.IsNullOrEmpty(source))return new byte[0];List<byte> buff = new List<byte>();for (int i = 0; i < source.Length; i += 2){buff.Add(Convert.ToByte(source.Substring(i, 2), 16));}return buff.ToArray();}

4、获取byte[]指定的区域的数组，offset：首地址；count：个数

    public static byte[] GetBytes(this byte[] source, int offset, int count){byte[] buff = new byte[count];int total = offset + count;int index = 0;for (int i = offset; i < total; i++){buff[index] = source[i];index++;}return buff;}

5、byte转为十六进制字符串 并补位  

    public static string ToHexString(this byte b){return b.ToString("X2");}

6、指定byte[]区域内 转十六进制字符串

    public static string ToHexString(this byte[] datas, int offset, int count){StringBuilder str = new StringBuilder();int total = offset + count;for (int i = offset; i < total; i++){str.Append(datas[i].ToString("X2"));}return str.ToString();}

7、byte转int字符串

    public static string ToIntString(this byte b){return b.ToString("D");}

8、byte[]转int字符串

    public static string ToIntString(this byte[] datas, int offset, int count){StringBuilder str = new StringBuilder();int total = offset + count;for (int i = offset; i < total; i++){str.Append(datas[i].ToString("D"));}return str.ToString();}

9、byte[]转int字符串，split：分割字符串

    public static string ToIntString(this byte[] datas, int offset, int count, string split = ""){StringBuilder str = new StringBuilder();int total = offset + count;for (int i = offset; i < total; i++){if (i > offset){str.Append(split);}str.Append(datas[i].ToString("D"));}return str.ToString();}

10、整形转byte[]数组：BitConverter.GetBytes，低位在前，高位在后；以字节数组的形式返回指定的 32 位有符号整数值。返回为4的字节数组

int iResult = 20000;
byte[] array = BitConverter.GetBytes(iResult);

11、byte[]数组转整形：BitConverter.ToInt32，低位在前，高位在后

byte[] array = new byte[4]{0x01,0x02,0x03,0x04};
BitConverter.ToInt32(datas,array);

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