C# - How can I do a simple query in Entity Framework using lambda?

Question

I have an Entity Framework model semi-working right now, but I'm having trouble performing a query to return database records with a Where() clause.

I am trying to line:

db.BlackstoneUsers.Where(u => u.Email == User.Email);

but I get the exception:

Expression cannot contain lambda expressions

I think this should be simple, but I'm just learning Entity and LINQ/Lambda.

Does anyone have any pointers?

What is User or User.Email? Is it just a straight string, or is it some sort of database object as well? — Steven V
– Steven V, Commented Jul 17, 2013 at 20:43
@StevenVondruska User is a database model and User.Email is a string — Brett
– Brett, Commented Jul 17, 2013 at 20:44
Are you trying to check this in the watch window in the debugger? The debugger doesn't support lambda expressions. — fcuesta
– fcuesta, Commented Jul 17, 2013 at 20:49

Kyle · Accepted Answer · 2013-07-17 20:45:53Z

1

try setting the email outside the call

var email = User.Email
db.BlackstoneUsers.Where(u => u.Email == email);

answered Jul 17, 2013 at 20:45

Kyle

1,1721 gold badge8 silver badges23 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Jeroen Vannevel Over a year ago

What would this accomplish?

Kyle Over a year ago

@JeroenVannevel the email would be converted to a constantexpression which can be translated by the EntityFramework code

Kyle Over a year ago

@brett only send constants to your EntityFramework expressions

Labrinths · Accepted Answer · 2013-07-17 21:05:07Z

0

Your code looks fine but what are you doing with the object?

Just this code will not work.

db.BlackstoneUsers.Where(u => u.Email == email);

But what if you do like

var something = db.BlackstoneUsers.Where(u => u.Email == User.email);

answered Jul 17, 2013 at 21:05

Labrinths

1301 silver badge11 bronze badges

Collectives™ on Stack Overflow

C# - How can I do a simple query in Entity Framework using lambda?

2 Answers 2

3 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related