Handle DBNull in C#

Question

Is there a better/cleaner way to do this?

int stockvalue = 0;
if (!Convert.IsDBNull(reader[\"StockValue\"]))
    stockvalue = (int)reader[\"StockValue\"];
         


        

Answer 1

Yes you can use int? This way you can have a default value of null instead of 0. Since the result of stockvalue could potentially be 0 there isn't confusion as to whether the database was 0 or null. For instance like this (pre nullable) we had a default initialization of -1 to represent no value was assigned. Personally, I thought this was a little dangerous because if you forget to set it to -1, there is a data corruption issue that can be really difficult to track down.

http://msdn.microsoft.com/en-us/library/2cf62fcy(VS.80).aspx

int? stockvalue = null;

if (!Convert.IsDBNull(reader["StockValue"]))
    stockvalue = (int)reader["StockValue"];

//Then you can check 

if(stockValue.HasValue)
{
  // do something here.
}