c# – 将(长尾数)和(sbyte指数)转换为十进制

我需要将尾数和指数转换为十进制.
这是我编码的方式：

// long field.Decimal.Mantissa
// sbyte field.Decimal.Exponent
decimal MDEntryPx = field.Decimal.Mantissa * (decimal)(Math.Pow(10,field.Decimal.Exponent));

field.Decimal.Mantissa是整数
但是Math.Pow(10,field.Decimal.Exponent)是双倍的,所以我担心在转换为十进制时我会丢失精度.

我应该为将产生十进制的整数类型编写自己的Pow函数吗？

你会建议什么？我关心性能,因为我称这个函数每秒数十万次！如此丑陋但快速的解决方案是非常需要的！

当我在这里工作时,我关心精确度.

这就是我刚刚编写的内容,但可能有人可以提出更好的建议：

class Util
{
    private static readonly decimal[] posPow10 = {
                                           1M,10M,100M,1000M,10000M,100000M,1000000M,10000000M,100000000M,1000000000M,10000000000M,100000000000M
                                       };

    private static readonly decimal[] negPow10 = {
                                           1M,0.1M,0.01M,0.001M,0.0001M,0.00001M,0.000001M,0.0000001M,0.00000001M,0.000000001M,0.0000000001M,0.00000000001M,};


    public static decimal Pow(decimal mantissa,sbyte exponent)
    {
        decimal result = mantissa;
        if (exponent >= 0)
        {
            result *= posPow10[exponent];
        } else {
            result *= negPow10[-exponent];
        }
        return result;
    }
}