What should I use to compare DBNull ? Using DBNull.Value or ToString().IsNullOrEmpty()

.net null dataset dbnull
Shantanu Gupta picture Shantanu Gupta · Aug 3, 2010 · Viewed 15.7k times · Source

I can check for a DBnull on a data row using any of the methods.

Either by using 

if(dr[0][0]==DBNull.Value)
//do somethin

or by doing

if(dr[0][0].ToString().IsNullOrEmpty())
//do something

In Both Cases I will be getting same result.

But Which one is conecptually right approach. Which was will use less resources

Answer

Fyodor Soikin picture Fyodor Soikin · Aug 3, 2010

The first way is somewhat correct. However, more accepted way is:

if ( dr[0][0] is DBNull )

And the second way is definitely incorrect. If you use the second way, you will get true in two cases:

  1. Your value is DBNull
  2. Your value is an empty string

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