1.支付服务端统一传的类型是 NSString

2.本地存的类型是 double

3.涉及到 乘法和除法使用

//两个double相乘- (double)numberMeetWith:(double)num1 andNum:(double)num2 {    NSDecimalNumberHandler *handler = [NSDecimalNumberHandler decimalNumberHandlerWithRoundingMode:NSRoundBankers                                                                                             scale:2                                                                                  raiseOnExactness:NO                                                                                   raiseOnOverflow:NO                                                                                  raiseOnUnderflow:NO                                                                               raiseOnDivideByZero:YES];    NSDecimalNumber *dec1 = [NSDecimalNumber decimalNumberWithString:[NSString stringWithFormat:@"%f",num1]];    NSDecimalNumber *dec2 = [NSDecimalNumber decimalNumberWithString:[NSString stringWithFormat:@"%f",num2]];    NSDecimalNumber *multiplyResult = [dec1 decimalNumberByMultiplyingBy:dec2                                                            withBehavior:handler];    return [multiplyResult doubleValue];}//两个double相除- (double)numberDivisionWith:(double)num1 andNum:(double)num2 {    NSDecimalNumberHandler *handler = [NSDecimalNumberHandler decimalNumberHandlerWithRoundingMode:NSRoundBankers                                                                                             scale:2                                                                                  raiseOnExactness:NO                                                                                   raiseOnOverflow:NO                                                                                  raiseOnUnderflow:NO                                                                               raiseOnDivideByZero:YES];    NSDecimalNumber *dec1 = [NSDecimalNumber decimalNumberWithString:[NSString stringWithFormat:@"%f",num1]];    NSDecimalNumber *dec2 = [NSDecimalNumber decimalNumberWithString:[NSString stringWithFormat:@"%f",num2]];    NSDecimalNumber *multiplyResult = [dec1 decimalNumberByDividingBy:dec2                                                            withBehavior:handler];    return [multiplyResult doubleValue];}

4.double去零

- (NSString *)stringDisposeWithFloat:(double)floatValue{    NSString *str = [NSString stringWithFormat:@"%f",floatValue];    long len = str.length;    for (int i = 0; i < len; i++)    {        if (![str  hasSuffix:@"0"])            break;        else            str = [str substringToIndex:[str length]-1];    }    if ([str hasSuffix:@"."])//避免像2.0000这样的被解析成2.    {        //s.substring(0, len - i - 1);        return [str substringToIndex:[str length]-1];    }    else    {        return str;    }}

5.使用示例

AppDelegate *app = (AppDelegate*)[[UIApplication sharedApplication] delegate];double iphoneDayPrice = [self numberMeetWith:app.QZBIphoneOutTimeDayPrice andNum:[ordModel.outTimeDay doubleValue]];double needAllMoney = iphoneDayPrice + [ordModel.repurchaseAmount doubleValue] - [self.orderDetailModel.repurchaseOffsetAmount doubleValue];//转成NSString[self stringDisposeWithFloat:app.QZBIphoneOutTimeDayPrice]