mirror of
https://github.com/Alex-Rachel/TEngine.git
synced 2025-08-14 16:51:28 +00:00
34 lines
925 B
C#
34 lines
925 B
C#
using System;
|
|
using System.Text;
|
|
|
|
namespace ET
|
|
{
|
|
public static class StringHashHelper
|
|
{
|
|
// bkdr hash
|
|
public static long GetLongHashCode(this string str)
|
|
{
|
|
const uint seed = 1313; // 31 131 1313 13131 131313 etc..
|
|
|
|
ulong hash = 0;
|
|
for (int i = 0; i < str.Length; ++i)
|
|
{
|
|
char c = str[i];
|
|
byte high = (byte)(c >> 8);
|
|
byte low = (byte)(c & byte.MaxValue);
|
|
hash = hash * seed + high;
|
|
hash = hash * seed + low;
|
|
}
|
|
return (long)hash;
|
|
}
|
|
|
|
public static int Mode(this string strText, int mode)
|
|
{
|
|
if (mode <= 0)
|
|
{
|
|
throw new Exception($"string mode < 0: {strText} {mode}");
|
|
}
|
|
return (int)((ulong)strText.GetLongHashCode() % (uint)mode);
|
|
}
|
|
}
|
|
} |