ADO.NET :: Can Get A Value Or Null From An Entity Query
Mar 28, 2011
Dim p = From i In context.persons
Order By i.fileNum
Select i.ID, i.fileNum, i.firstName, i.lastName, i.state, i.prPenPals.FirstOrDefault.startProfile, i.prPenPals.FirstOrDefault.endProfile
where for every person, prPenPal can have exactly one or zero records? I can do the above, but when I try to use p as the datasource of a ListView I get The cast to value type 'DateTime' failed because the materialized value is null. Either the result type's generic parameter or the query must use a nullable type.
I tried using
Select i.inmateID, i.fileNum, i.firstName, i.lastName, i.state, i.prLegals.FirstOrDefault.startProfile.ToString,
i.prLegals.FirstOrDefault.endProfile.ToString
but that didn't work. I got a blue squiggly line "Range variable name cannot match the name of a member of the 'Object' class" error I want the date if the record exists, and Null or Nothing if it dosen't.
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