What is an efficient way to check the precision and scale of a numeric value?

Question

I'm writing a routine that validates data before inserting it into a database, and one of the steps is to see if numeric values fit the precision and scale of a Numeric(x,y) SQL-Server type.

I have the precision and scale from SQL-Server already, but what's the most efficient way in C# to get the precision and scale of a CLR value, or at least to test if it fits a given constraint?

At the moment, I'm converting the CLR value to a string, then looking for the location of the decimal point with .IndexOf(). Is there a faster way?

Answer 1

You can use decimal.Truncate(val) to get the integral part of the value and decimal.Remainder(val, 1) to get the part after the decimal point and then check that each part meets your constraints (I'm guessing this can be a simple > or < check)

Answer 2

System.Data.SqlTypes.SqlDecimal.ConvertToPrecScale( new SqlDecimal (1234.56789), 8, 2)

gives 1234.67. it will truncate extra digits after the decimal place, and will throw an error rather than try to truncate digits before the decimal place (i.e. ConvertToPrecScale(12344234, 5,2)