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c#globalization

Parsing decimal with thousands separator


I have the following block of code:

string price = "1,234.56";
decimal value = 0;
var allowedStyles = (NumberStyles.AllowDecimalPoint & NumberStyles.AllowThousands);

if (Decimal.TryParse(price, allowedStyles, CultureInfo.InvariantCulture, out value))
{
    Console.log("Thank you!");
}
else
{
    throw new InvalidFormatException();
}

Ultimately, price will either be in US style (i.e. 1,234.56) or German style (i.e. 1.234,56). My challenge is right now, Decimal.TryParse fails. I suspect its because of the thousands separator. Which is why I added the allowedStyles variable.

What am I doing wrong?


Solution

  • If you AND-combine the NumberStyles-flag, you will get None.

    00100000 (AllowDecimalPoint)
    &
    01000000 (AllowThousands)
    --------
    00000000 (None)
    

    Try to OR-combine them: NumberStyles.AllowDecimalPoint | NumberStyles.AllowThousands

    00100000 (AllowDecimalPoint)
    |
    01000000 (AllowThousands)
    --------
    01100000 (AllowDecimalPoint, AllowThousands)
    

    Additionally, I'm afraid that you can't parse both styles (US style and DE style) with one statement.

    So I'd try both:

    string price = "1,234.56";
    decimal value = 0;
    var allowedStyles = (NumberStyles.AllowDecimalPoint | NumberStyles.AllowThousands);
    
    if (Decimal.TryParse(price, allowedStyles, CultureInfo.GetCultureInfo("DE-de"), out value))
    {
        Console.Write("Danke!");
    }
    else if (Decimal.TryParse(price, allowedStyles, CultureInfo.GetCultureInfo("EN-us"), out value))
    {
        Console.Write("Thank you!");
    }
    else
    {
        throw new InvalidFormatException();
    }