方法一,
long s = 99999999999999;
string s1 = Base62Encode(s);
long s2 = Base62Decode(s1);
static string Base62Encode(long num)
{
string s = “”;
while (num != 0)
{
s = tenValue2Char(num % 62).ToString() + s;
num = num / 62;
}
return s;
}
static string tenValue2Char(long ten)
{
if (ten < 10) return ten.ToString();
if (ten >= 10 && ten <= 36) return Convert.ToChar(ten + 87).ToString();
if (ten >= 37 && ten <= 61) return Convert.ToChar(ten – 29).ToString();
return “”;
}
static long Base62Decode(string hex)
{
long l = 0;
for (int i = 0; i < hex.Length; i++)
{
l = l + (long)HexChar2Value(hex[i]) * (long)Math.Pow((double)62, (double)(hex.Length – i – 1));
}
return l;
}
static int HexChar2Value(char hexChar)
{
if (hexChar >= 97 && hexChar <= 122) return hexChar – 87;
if (hexChar >= 65 && hexChar <= 90) return hexChar – 29;
return Convert.ToInt32(hexChar.ToString());
}
方法二,
long s = 99999999999999;
string s1 = Base62Encode(s);
long s2 = Base62Decode(s1);
static string Base62Encode(long num)
{
string s = "";
while (num != 0)
{
s = tenValue2Char(num % 62).ToString() + s;
num = num / 62;
}
return s;
}
static string tenValue2Char(long ten)
{
switch (ten)
{
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
case 6:
case 7:
case 8:
case 9:
return ten.ToString();
case 10: return "a";
case 11: return "b";
case 12: return "c";
case 13: return "d";
case 14: return "e";
case 15: return "f";
case 16: return "g";
case 17: return "h";
case 18: return "i";
case 19: return "j";
case 20: return "k";
case 21: return "l";
case 22: return "m";
case 23: return "n";
case 24: return "o";
case 25: return "p";
case 26: return "q";
case 27: return "r";
case 28: return "s";
case 29: return "t";
case 30: return "u";
case 31: return "v";
case 32: return "w";
case 33: return "x";
case 34: return "y";
case 35: return "z";
case 36: return "A";
case 37: return "B";
case 38: return "C";
case 39: return "D";
case 40: return "E";
case 41: return "F";
case 42: return "G";
case 43: return "H";
case 44: return "I";
case 45: return "J";
case 46: return "K";
case 47: return "L";
case 48: return "M";
case 49: return "N";
case 50: return "O";
case 51: return "P";
case 52: return "Q";
case 53: return "R";
case 54: return "S";
case 55: return "T";
case 56: return "U";
case 57: return "V";
case 58: return "W";
case 59: return "X";
case 60: return "Y";
case 61: return "Z";
default: return "";
}
}
static long Base62Decode(string hex)
{
long l = 0;
for (int i = 0; i < hex.Length; i++)
{
l = l + (long)HexChar2Value(hex[i]) * (long)Math.Pow((double)62, (double)(hex.Length - i - 1));
}
return l;
}
static int HexChar2Value(char hexChar)
{
switch (hexChar)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
return Convert.ToInt32(hexChar.ToString());
case 'a': return 10;
case 'b': return 11;
case 'c': return 12;
case 'd': return 13;
case 'e': return 14;
case 'f': return 15;
case 'g': return 16;
case 'h': return 17;
case 'i': return 18;
case 'j': return 19;
case 'k': return 20;
case 'l': return 21;
case 'm': return 22;
case 'n': return 23;
case 'o': return 24;
case 'p': return 25;
case 'q': return 26;
case 'r': return 27;
case 's': return 28;
case 't': return 29;
case 'u': return 30;
case 'v': return 31;
case 'w': return 32;
case 'x': return 33;
case 'y': return 34;
case 'z': return 35;
case 'A': return 36;
case 'B': return 37;
case 'C': return 38;
case 'D': return 39;
case 'E': return 40;
case 'F': return 41;
case 'G': return 42;
case 'H': return 43;
case 'I': return 44;
case 'J': return 45;
case 'K': return 46;
case 'L': return 47;
case 'M': return 48;
case 'N': return 49;
case 'O': return 50;
case 'P': return 51;
case 'Q': return 52;
case 'R': return 53;
case 'S': return 54;
case 'T': return 55;
case 'U': return 56;
case 'V': return 57;
case 'W': return 58;
case 'X': return 59;
case 'Y': return 60;
case 'Z': return 61;
default:
return 0;
}
}方法三，System.Linq
long s = 99999999999999;
string s1 = Base62Encode(s);
long s2 = Base62Decode(s1);
static
string
Base62Encode(
long
num)
{
string
s =
""
;
char
[] metachar = Enumerable.Range(0, 10).Select(x => (
char
)(
'0'
+ x))
.Concat(Enumerable.Range(0, 26).Select(x => (
char
)(
'a'
+ x)))
.Concat(Enumerable.Range(0, 26).Select(x => (
char
)(
'A'
+ x)))
.ToArray();
while
(num != 0)
{
s = metachar[num % 62].ToString() + s;
num = num / 62;
}
return
s;
}
static
long
Base62Decode(
string
s)
{
var dict = Enumerable.Range(0, 10).Select(x => (
char
)(
'0'
+ x))
.Concat(Enumerable.Range(0, 26).Select(x => (
char
)(
'a'
+ x)))
.Concat(Enumerable.Range(0, 26).Select(x => (
char
)(
'A'
+ x)))
.Select((x, i) =>
new
{ x, i }).ToDictionary(x => x.x, x => x.i);
long
l = 0;
for
(
int
i = 0; i < s.Length; i++)
{
l = l + (
long
)dict[s[i]] * (
long
)Math.Pow((
double
)62, (
double
)(s.Length - i - 1));
}
return
l;
}
