Handle DBNull in C#

c# datareader dbnull
Andreas picture Andreas · Mar 12, 2010 · Viewed 41.8k times · Source

Is there a better/cleaner way to do this?

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

Answer

Philippe Leybaert picture Philippe Leybaert · Mar 12, 2010

The shortest (IMHO) is:

int stockvalue = (reader["StockValue"] as int?) ?? 0;

Explanation:

  • If reader["StockValue"] is of type int, the value will be returned, and the "??" operator will return the result
  • If reader["StockValue"] is NOT of type int (e.g. DBNull), null will be returned, and the "??" operator will return the value 0 (zero).

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