翻倍。有N个小数位数的ToString。

I know that if we want to display a double as a two decimal digit, one would just have to use

我知道如果我们想要显示一个两位数的两位数，就只能用。

public void DisplayTwoDecimal(double dbValue)
{
  Console.WriteLine(dbValue.ToString("0.00"));
}

But how to extend this to N decimal places, where N is determined by the user?

但是如何将它扩展到N位小数，其中N是由用户决定的?

 public void DisplayNDecimal(double dbValue, int nDecimal)
    {
     // how to display
    }

2 个解决方案

#1

Use "Nx" for x decimal digits.

用“Nx”表示x十进制数字。

 public void DisplayNDecimal(double dbValue, int nDecimal)
 {
   Console.WriteLine(dbValue.ToString("N" + nDecimal));
 }

#2

-4

I would use this:

我想用这个:

public string DisplayNDecimal(double dbValue, int nDecimal)
{
    string decimalPoints = "0";
    if (nDecimal > 0)
    {
        decimalPoints += ".";
        for (int i = 0; i < nDecimal; i++)
            decimalPoints += "0";
    }
    return dbValue.ToString(decimalPoints);
}

Here is it with StringBuilder (though probably not more efficient and definitely would require more resources)

这里是StringBuilder(尽管可能不是更高效，而且绝对需要更多的资源)

public string DisplayNDecimal(double dbValue, int nDecimal)
{
    StringBuilder decimalPoints = new StringBuilder("0");
    if (nDecimal > 0)
    {
        decimalPoints.Append(".");
        for (int i = 0; i < nDecimal; i++)
            decimalPoints.Append("0");
    }
    return dbValue.ToString(decimalPoints.ToString());
}

#1