Question

I create a function to compare the price of my item.
This is my function:

public static decimal ComparePrice(decimal Price, decimal WebsitePrice)
    {
        decimal ZERO_PRICE = 0.00000M;
        if(Price == ZERO_PRICE && WebsitePrice > ZERO_PRICE){
            return WebsitePrice;
        }else if(Price == ZERO_PRICE && WebsitePrice == ZERO_PRICE){
            return "";
        }else{
            return Price;
        }

    }

if the both(price and websiteprice) is equal 0.00, then it will return the empty string, I know it is not possible to return the string while the function is set to decimal type, but i have no idea what should I do about that. Anyone can help? Thanks.

Answer 1

If it makes sense in your application logic, you can use a Nullable type and use null instead of an empty string. Like :

public static decimal? ComparePrice(decimal Price, decimal WebsitePrice)
    {
        if(Price == decimal.Zero && WebsitePrice > decimal.Zero){
            return WebsitePrice;
        }else if(Price == decimal.Zero && WebsitePrice == decimal.Zero){
            return null;
        }else{
            return Price;
        }

    }

Or use Decimal.MinValue as suggested as a flag for invalid. (I like the null better, again, just if this is actually a valid value in your logic).