Check null values in Linq query in Entity Framework

Question

How can I compare integer type null values Where portion of Linq query in .Net Entity framework 4.1?

Wouter de Kort · Accepted Answer · 2012-01-18 15:43:37Z

12

You can only compare an int to NULL if the int is nullable. If not, the default value for int will be 0 and never null.

You define a nullable int property like this:

int? value { get; set; }

And check it like this:

if ( value != null )
{
   int x = value.Value;
}

In the where clause of a Linq query it would be

var result = from d in data
             where d.Value != null
             select d

answered Jan 18, 2012 at 15:43

Wouter de Kort♦

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Comments

Devin Burke · Accepted Answer · 2012-01-18 16:01:44Z

7

If you are comparing to a null value, you must first compare your value to null due to a bug.

var field = from field in table
            where (value == null ? field.property == null : field.property == value)
            select field;

answered Jan 18, 2012 at 15:45

Devin Burke

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