Getting an error while using partial updates in asp .net Web API

Question

I am following this tutorial(What's the currently recommended way of performing partial updates with Web API?) to implement partial updates in my web api. But doing so i am getting an error:

  Cannot convert lambda expression to type 'object[]' because it is not a delegate type

This is my code for partial updates/patch :

   [AcceptVerbs("PATCH")]
    public user PatchDocument(int id, Delta <user> user)
    {
        var serverUser =db.users.Find(u => u.iduser = id); // This is where i get error Find(u => u.iduser = id)
        user.Patch(serverUser);

    }

`u.iduser = id` should that be `u.iduser == id`. Single `=` is assignment. — Kami, Oct 02 '13 at 09:43
Can you show us what `db.users` contain? And, by the way, why does your method signature say you return a `user` while the code seems to return nothing? Are you still getting the error on the same line of code? — Halvard, Oct 02 '13 at 10:04

Adween · Accepted Answer · 2013-10-02T09:53:05.087

2

you could try

var serverUser =db.users.FirstOrDefault(u => u.iduser == id);
if(serverUser != null)
{
    user.Patch(serverUser);
}

Edit Whoops needed ==

edited Oct 02 '13 at 09:53

answered Oct 02 '13 at 09:40

Adween

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I am getting this error while using your code : Cannot convert lambda expression to delegate type 'System.Func' because some of the return types in the block are not implicitly convertible to the delegate return type – Obvious Oct 02 '13 at 09:45
And Cannot implicitly convert type 'int' to 'bool' – Obvious Oct 02 '13 at 09:46
@Hmmmmmmmmmm Could you try Adween's suggestion again (after he changed to ==)? – Halvard Oct 02 '13 at 10:05
Error has changed now, now i am getting : not all code paths return a value – Obvious Oct 02 '13 at 10:07
Yep @Halvard, i tried, now error is changed :not all code paths return a value – Obvious Oct 02 '13 at 10:08
@Hmmmmmmmmmm This is because you return nothing but your method signature says you need to return `user`. – Halvard Oct 02 '13 at 10:10

score 0 · Answer 2 · answered Oct 02 '13 at 09:49

0

Try this:

var serverUser = db.users.Find(u => u.iduser == id);  // == instead of =

answered Oct 02 '13 at 09:49

Halvard

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Cannot convert lambda expression to type 'object[]' because it is not a delegate type – Obvious Oct 02 '13 at 09:53
1

Ok, so it did not fix the main error, but even so you need to use == instead of = – Halvard Oct 02 '13 at 09:58
True , it was a mistake. – Obvious Oct 02 '13 at 09:59

Getting an error while using partial updates in asp .net Web API

2 Answers2