Question

I have a string mystring that the user enters. I check that it is a valid decimal thus

decimal val;
bool validDecimal = decimal.TryParse(mystring, out val);
if (!validDecimal)
   isvalid = false;

But this is not the only validation I need to do. I also need to check that this decimal is specified to 2 decimal places or less

so,

23, 23.1, 23.45

are all valid

but

23.345, 23.450

are not.

What’s the best way to do this?

Answer 1

How about string parsing.

static bool LessThan2DecimalPlaces(string mystring, out decimal val)
{
    bool validDecimal = decimal.TryParse(mystring, out val);
    if (!validDecimal)
    {
       return false;
    }

   var index = mystring.LastIndexOf(NumberFormatInfo.CurrentInfo.NumberDecimalSeparator);
   if(index == -1)
   {
       return true;
   }
   return mystring.Substring(index).Count() < 3
}