----Rounding issues for iOS development

Http://blog.sina.com.cn/s/blog_71715bf801017nyw.html

Method One:

-(NSString *) notrounding: (float) Price afterpoint: (int) position{

nsdecimalnumberhandler* Roundingbehavior = [Nsdecimalnumberhandler decimalnumberhandlerwithroundingmode: Nsrounddown scale:position raiseonexactness:no raiseonoverflow:no raiseonunderflow:no RaiseOnDivideByZero:NO];

Nsdecimalnumber *ouncesdecimal;

Nsdecimalnumber *roundedounces;

Ouncesdecimal = [[Nsdecimalnumber alloc] initwithfloat:price];

Roundedounces = [Ouncesdecimal decimalnumberbyroundingaccordingtobehavior:roundingbehavior];

[Ouncesdecimal release];

return [NSString stringwithformat:@ "%@", roundedounces];

}

Explain the parameters:

Price: Numbers that need to be processed,

Position: Keep the decimal point,

and then call

float s = 0.126;

NSString *SV = [self notrounding:s afterpoint:2];

NSLog (@ "SV =%@", SV);

The output is: SV = 0.12

The following describes the key parameters of Nsdecimalnumberhandler initialization: Decimalnumberhandlerwithroundingmode:nsrounddown,

The Nsrounddown represents is only to be placed.

The parameter position of scale represents a few digits after the decimal point is retained.

What do I do if I just get into it, for example, float 0.162 want 0.17? , there is a table on the development document that is treated as a reserved decimal point. I believe that we can see the following:

Method Two:

1, round (12345.6789) results are: 12346

2, round (12345.6789*100)/100 Results: 12345.68

The second is the result I want, but I do not understand this simple rounding to make so complicated, there should be better, I remember in other languages with: round (12345.6789,2) can be rounded to two decimal places.

----Rounding issues for iOS development