NSDecimalNumber用法-处理金额显示问题

NSDecimalNumber用来处理iOS中金额显示问题，可以转换string类型，也可以将int类型转换成Number然后转为NSDecimalNumber

NSDecimalNumber*priceDecimalNum = [NSDecimalNumber decimalNumberWithString:priceStr];

//将数量转为NSDecimal

NSDecimal countDec = [[NSNumber numberWithInteger:model.countNum]decimalValue];

//单价x数量

priceDecimalNum = [priceDecimalNum decimalNumberByMultiplyingBy:[NSDecimalNumber decimalNumberWithDecimal:countDec]];

//折扣后总价

 totalPrice = [totalPricedecimal NumberByAdding:priceDecimalNum];

//原商品总价

NSDecimalNumber *oriDecimalNum = [NSDecimalNumber decimalNumberWithString:model.productPrice];

oriDecimalNum = [oriDecimalNum decimalNumberByMultiplyingBy:[NSDecimalNumber decimalNumberWithDecimal:countDec]];

oriTotalPrice = [oriTotalPrice decimalNumberByAdding:oriDecimalNum];