问题
Why
Console.WriteLine((1000000f + 0.10f).ToString("N2"));
1 000 000.00
but no 1 000 000.10?
When I use type "double" or type "float" less 1000000 - this problem disappears!
回答1:
Use decimal to prevent those accuracy/rounding issues.
Console.WriteLine((1000000m + 0.10m).ToString("N2"));
Reason: float has only a accuracy of 7 digits (reference) - your number has 8
回答2:
According to MSDN, float type has only 7 digits precision. One milion has 7 digits, decimal part is rounded.
Double type has 15 - 16 digits precision, so milion can have 8 - 9 digits long decimal part. Number less than one milion has less than 7 digits (without decimal part).
来源：https://stackoverflow.com/questions/42271635/c-sharp-float-trouble-why-1000000-0-10f-1000000