Expression with contains , giving error like "Object reference not set to an instance of an object"

Question

When I Using C# linq expression with contains , I got an Error like "Object reference not set to an instance of an object". My Code Segement is,

var query = GetUserDataForList();// It contains the data I want
 search = (search == null) ? "" : search;
 string searchText = (search == null) ? "" : search.ToLower().ToString();

 var users = query.Where(a => a.Email.ToLower().Contains(searchText) && a.Email != null).AsEnumerable();
 users = users.Skip(rowsPerPage * (page - 1)).Take(rowsPerPage).AsEnumerable();

any idea how to solve that?

[What is a NullReferenceException and how do I fix it?](http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-and-how-do-i-fix-it) — Soner Gönül, Jan 05 '15 at 16:31
In your where clause you are performing your null check after accessing the property, change it to `Where(a => a.Email != null && a.Email.ToLower().Contains(searchText))` — Ben Robinson, Jan 05 '15 at 16:34

score 4 · Answer 1 · answered Jan 05 '15 at 16:33

Your conditions in Where clause should be like:

a.Email != null && a.Email.ToLower().Contains(searchText)

Because only then it will short-circuit in case of null. Right now even if your Email is null it will try to use use ToLower and give you NRE.

See: && Operator (C# Reference)

The conditional-AND operator (&&) performs a logical-AND of its bool operands, but only evaluates its second operand if necessary

Expression with contains , giving error like "Object reference not set to an instance of an object"

1 Answers1