.NET Core中每次程式啟動通過系統內建的 GetHashCode 獲取到的都不同，可通過下面的演算法獲取到的雜湊值持久化不變。

var str = "1";
            Console.WriteLine(str.GetHashCode());
            var str2 = "1";
            Console.WriteLine(str2.GetHashCode());
            Console.WriteLine("-------------------------------");

            var str3 = "
 
2";
            Console.WriteLine(str3.GetExtHashCode());
            var str4 = "2";
            Console.WriteLine(str4.GetExtHashCode());

            Console.ReadKey();

   public static class HashExtends
    {
        public static int GetExtHashCode(this string str)
        {
            unchecked
 

            {
                int hash1 = (5381 << 16) + 5381;
                int hash2 = hash1;
                for (int i = 0; i < str.Length; i += 2)
                {
                    hash1 = ((hash1 << 5) + hash1) ^ str[i];
                    if (i == str.Length - 1)
                        
 
break;
                    hash2 = ((hash2 << 5) + hash2) ^ str[i + 1];
                }
                return hash1 + (hash2 * 1566083941);
            }
        }
    }

支援作者原創來源：https://codedefault.com/p/why-is-string-gethashcode-method-get-difference-hash-code-when-restart-aspnet-core-application