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LINQ syntax where string value is not null or empty

Asked 2009-09-02T16:59:28.617
55

I'm trying to do a query like so...

query.Where(x => !string.IsNullOrEmpty(x.PropertyName));

but it fails...

so for now I have implemented the following, which works...

query.Where(x => (x.PropertyName ?? string.Empty) != string.Empty);

is there a better (more native?) way that LINQ handles this?

EDIT

apologize! didn't include the provider... This is using LINQ to SQL

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This will work fine with Linq to Objects. However, some LINQ providers have difficulty running CLR methods as part of the query. This is expecially true of some database providers.

The problem is that the DB providers try to move and compile the LINQ query as a database query, to prevent pulling all of the objects across the wire. This is a good thing, but does occasionally restrict the flexibility in your predicates.

Unfortunately, without checking the provider documentation, it's difficult to always know exactly what will or will not be supported directly in the provider. It looks like your provider allows comparisons, but not the string check. I'd guess that, in your case, this is probably about as good of an approach as you can get. (It's really not that different from the IsNullOrEmpty check, other than creating the "string.Empty" instance for comparison, but that's minor.)

answered 2009-09-02T17:06:49.087

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