Find object that meets multiple conditions using LINQ

Question

I am trying to find an object in my database that meets two conditions, I did a search on stackoverflow and found this one which looks exactly like what I need. However, I have this code:

if (db.MinimumProductInfo.Find(pc => pc.ItemCode == productInfoWithNote.ItemCode && pc.Region == productInfoWithNote.Region))

and I am receiving this error:

Cannot Convert Lambda Expression to type 'object[]' because it is not a delegate type.

MinimumProductInfo is my class and productInfoWithNote is the viewmodel that I pass in to the method.

`Find` is for locating by primary key. I think you want to use `Where` — stephen.vakil, Oct 04 '17 at 19:41
@stephen.vakil Find() actually only works on List while Where() works on an IEnumerable, but yes I agree it should be changed — RH6, Oct 04 '17 at 19:44
@RH6 I assumed it was an attempt to use [`DbSet.Find`](https://msdn.microsoft.com/en-us/library/gg696418(v=vs.113).aspx) (which seems to match the error) — stephen.vakil, Oct 04 '17 at 19:48
@stephen.vakil dbSet.Find() is a different method than the Linq Find() method — RH6, Oct 04 '17 at 19:50
@RH6 The code is invoking the former, which expects `object[]` as the parameter, not a predicate. Thus the error. — stephen.vakil, Oct 04 '17 at 19:54
Where is `Find()` coming from? I see nothing in `System.Linq`. — mxmissile, Oct 04 '17 at 19:56
LINQ doesn't have a `Find` method. This is about instance methods of `List` and `DbSet`. — Gert Arnold, Oct 04 '17 at 19:57

Abdullah Dibas · Accepted Answer · 2017-10-04T19:53:51.270

1

Try using FirstOrDefault which will return null if no object meets the conditions:

 var myObject = db.MinimumProductInfo.FirstOrDefault(pc => pc.ItemCode == 
        productInfoWithNote.ItemCode && pc.Region == productInfoWithNote.Region);

    if(myObject != null)
    {
         // use your object here
    }

NOTE: Find method returns the first match element if exists and if not it will return the default value of element's type and you are using it like it will return a boolean value.

edited Oct 04 '17 at 19:53

answered Oct 04 '17 at 19:44

Abdullah Dibas

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don't use `object`. Write the actual type or `var` – Gilad Green Oct 04 '17 at 19:50

Find object that meets multiple conditions using LINQ

1 Answers1