c＃中的数学四舍五入 - 整数问题

Question

<%= Math.Round(keyRate, 5) %>

So in our view, we use this to display a bunch of numbers. it seems when we have a whole number, it rounds to 2 decimals instead of 5. Is this expected behavior? If so, how would I change it.

Thanks!

Answer 1

There's a difference between what a number is and how it's displayed when written out. You may need to override ToString() with ToString(string)

Per the Custom Numeric Formats , if you want it to be 5 places, you would use

Math.Round(keyRate, 5).ToString(00.00000)

More information on the "0" custom specifier .

Answer 2

The second parameter to Math.Round(d, decimals) is the number of fractional digits that will be returned at most . From MSDN :

If the precision of d is less than decimals, d is returned unchanged .

In your case you are passing a number with less fractional digits, so it remains unchanged.

Answer 3

How do you know that it is rounding to 2 decimals while you are passing a whole number? My guess is that you are outputting only 2 decimals.