Test for a null value
Applies To: Dynamics CRM 2013
The following code example shows how to test for a null value by using the FilterExpression and QueryByAttribute classes.
Example
Use this code to test for equality by using the FilterExpression class.
FilterExpression null_filter = new FilterExpression(LogicalOperator.And);
null_filter.FilterOperator = LogicalOperator.And;
null_filter.AddCondition("leadid", ConditionOperator.Null);
Example
Use this code to test for inequality by using the FilterExpression class.
FilterExpression filter = new FilterExpression(LogicalOperator.And);
filter.FilterOperator = LogicalOperator.And;
filter.AddCondition("leadid", ConditionOperator.NotNull);
Example
Use this code to test for equality by using the QueryByAttribute class.
QueryByAttribute qba = new QueryByAttribute("account");
qba.ColumnSet = new ColumnSet("name","address1_stateorprovince");
qba.AddAttributeValue("donotfax", null);
See Also
Build queries with QueryExpression
Page large result sets with QueryExpression