iOS精确到小数点两位//格式话小数 四舍五入类型

- (NSString *) decimalwithFormat:(NSString *)format  floatV:(float)floatV

{

NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];

[numberFormatter setPositiveFormat:format];

return  [numberFormatter stringFromNumber:[NSNumber numberWithFloat:floatV]];

}