golang 将[]byte转成16进制的实现

将[]byte转成16进制

import 'crypto/md5'import 'fmt'sign := md5.Sum([]byte('date string'))signStr := fmt.Sprintf('%x', sign) //将[]byte转成16进制

补充：golang []byte存储存储的16进制转10进制

项目中有用[]byte存储16进制需要转到10进制，如果用系统自带的函数处理，需要先将[]byte通过hex.EncodeToString转为string，再用strconv.ParseInt转到10进制，过程中由于两次转换导致内存分配过多（每秒执行近100w次），GC出现错误导致进程挂掉。

自己写了一个函数来转，主要是避免出现内存泄漏：

var b2m_map map[byte]uint64 = map[byte]uint64{0x00: 0,0x01: 1,0x02: 2,0x03: 3,0x04: 4,0x05: 5,0x06: 6,0x07: 7,0x08: 8,0x09: 9,0x0A: 10,0x0B: 11,0x0C: 12,0x0D: 13,0x0E: 14,0x0F: 15,0x10: 16,0x11: 17,0x12: 18,0x13: 19,0x14: 20,0x15: 21,0x16: 22,0x17: 23,0x18: 24,0x19: 25,0x1A: 26,0x1B: 27,0x1C: 28,0x1D: 29,0x1E: 30,0x1F: 31,0x20: 32,0x21: 33,0x22: 34,0x23: 35,0x24: 36,0x25: 37,0x26: 38,0x27: 39,0x28: 40,0x29: 41,0x2A: 42,0x2B: 43,0x2C: 44,0x2D: 45,0x2E: 46,0x2F: 47,0x30: 48,0x31: 49,0x32: 50,0x33: 51,0x34: 52,0x35: 53,0x36: 54,0x37: 55,0x38: 56,0x39: 57,0x3A: 58,0x3B: 59,0x3C: 60,0x3D: 61,0x3E: 62,0x3F: 63,0x40: 64,0x41: 65,0x42: 66,0x43: 67,0x44: 68,0x45: 69,0x46: 70,0x47: 71,0x48: 72,0x49: 73,0x4A: 74,0x4B: 75,0x4C: 76,0x4D: 77,0x4E: 78,0x4F: 79,0x50: 80,0x51: 81,0x52: 82,0x53: 83,0x54: 84,0x55: 85,0x56: 86,0x57: 87,0x58: 88,0x59: 89,0x5A: 90,0x5B: 91,0x5C: 92,0x5D: 93,0x5E: 94,0x5F: 95,0x60: 96,0x61: 97,0x62: 98,0x63: 99,0x64: 100,0x65: 101,0x66: 102,0x67: 103,0x68: 104,0x69: 105,0x6A: 106,0x6B: 107,0x6C: 108,0x6D: 109,0x6E: 110,0x6F: 111,0x70: 112,0x71: 113,0x72: 114,0x73: 115,0x74: 116,0x75: 117,0x76: 118,0x77: 119,0x78: 120,0x79: 121,0x7A: 122,0x7B: 123,0x7C: 124,0x7D: 125,0x7E: 126,0x7F: 127,0x80: 128,0x81: 129,0x82: 130,0x83: 131,0x84: 132,0x85: 133,0x86: 134,0x87: 135,0x88: 136,0x89: 137,0x8A: 138,0x8B: 139,0x8C: 140,0x8D: 141,0x8E: 142,0x8F: 143,0x90: 144,0x91: 145,0x92: 146,0x93: 147,0x94: 148,0x95: 149,0x96: 150,0x97: 151,0x98: 152,0x99: 153,0x9A: 154,0x9B: 155,0x9C: 156,0x9D: 157,0x9E: 158,0x9F: 159,0xA0: 160,0xA1: 161,0xA2: 162,0xA3: 163,0xA4: 164,0xA5: 165,0xA6: 166,0xA7: 167,0xA8: 168,0xA9: 169,0xAA: 170,0xAB: 171,0xAC: 172,0xAD: 173,0xAE: 174,0xAF: 175,0xB0: 176,0xB1: 177,0xB2: 178,0xB3: 179,0xB4: 180,0xB5: 181,0xB6: 182,0xB7: 183,0xB8: 184,0xB9: 185,0xBA: 186,0xBB: 187,0xBC: 188,0xBD: 189,0xBE: 190,0xBF: 191,0xC0: 192,0xC1: 193,0xC2: 194,0xC3: 195,0xC4: 196,0xC5: 197,0xC6: 198,0xC7: 199,0xC8: 200,0xC9: 201,0xCA: 202,0xCB: 203,0xCC: 204,0xCD: 205,0xCE: 206,0xCF: 207,0xD0: 208,0xD1: 209,0xD2: 210,0xD3: 211,0xD4: 212,0xD5: 213,0xD6: 214,0xD7: 215,0xD8: 216,0xD9: 217,0xDA: 218,0xDB: 219,0xDC: 220,0xDD: 221,0xDE: 222,0xDF: 223,0xE0: 224,0xE1: 225,0xE2: 226,0xE3: 227,0xE4: 228,0xE5: 229,0xE6: 230,0xE7: 231,0xE8: 232,0xE9: 233,0xEA: 234,0xEB: 235,0xEC: 236,0xED: 237,0xEE: 238,0xEF: 239,0xF0: 240,0xF1: 241,0xF2: 242,0xF3: 243,0xF4: 244,0xF5: 245,0xF6: 246,0xF7: 247,0xF8: 248,0xF9: 249,0xFA: 250,0xFB: 251,0xFC: 252,0xFD: 253,0xFE: 254,0xFF: 255,}func hex2int(hexB *[]byte) uint64 {var retInt uint64hexLen := len(*hexB)for k, v := range *hexB {retInt += b2m_map[v] * exponent(16, uint64(2*(hexLen-k-1)))}return retInt}func exponent(a, n uint64) uint64 {result := uint64(1)for i := n; i > 0; i >>= 1 {if i&1 != 0 {result *= a}a *= a}return result}

经过测试，性能和自带的方法接近，略有提升。

goos: windowsgoarch: amd64pkg: benchmarkBenchmark_General-4 10000000 144 ns/opBenchmark_Better-4 10000000 128 ns/opPASSok benchmark3.086s

以上为个人经验，希望能给大家一个参考，也希望大家多多支持优爱好网。如有错误或未考虑完全的地方，望不吝赐教。