Select one item from each category on the basis of cost

Question

I want to select five item one from each category which are having lowest cost, i am getting an error please help me with this

     var packageId = objentity.PackageGalleries.
                Where(p => p.ParentCategory != "Indian" 
                        && p.ParentCategory != "International").
                OrderBy(p => p.PackageCost)
               .GroupBy(p => p.ParentCategory).FirstOrDefault();

it is only selecting one item from one category

In the view i m passing

     @foreach (var item in Model)
        {
            <a href="javascript:;">
                <img src="~/Content/JetJourney/img/@item.FileName" />

                <div>
                    <p>@item.PackageName, Starting Price @item.PackageCost *</p>
                   <br />
                </div>
            </a>
        }

_i am getting an error_ - What error? – Jan 15 '16 at 10:10 — , Jan 15 '16 at 10:10

score 1 · Accepted Answer · edited May 23 '17 at 12:15

1

You can group the data by ParentCategory and within that group order the grouped data by PackageCost. This should give you the expected output:-

    var packageId = objentity.PackageGalleries
                            .Where(p => p.ParentCategory != "Indian" &&       
                                        p.ParentCategory != "International")
                            .GroupBy(p => p.ParentCategory)
                            .Select(x => x.OrderBy(p => p.PackageCost).FirstOrDefault())
                            .ToList();

Update:

For your issue althought I have never experienced such issue but it may be due to deferred execution of LINQ as per this post. You can force execute the query using ToList() as updated.

edited May 23 '17 at 12:15

Community

1
1

answered Jan 15 '16 at 08:05

Rahul Singh

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@Richa - Really Sorry! Didn't read you question carefully (#IndVsAus you knw ;)). Check updated code. – Rahul Singh Jan 15 '16 at 08:18
thankyou, but giving an error "The operation cannot be completed because the DbContext has been disposed.". in the view – Richa Jan 15 '16 at 09:09
can you .ToList() method pls?[example](http://stackoverflow.com/questions/21212822/the-operation-cannot-be-completed-because-the-dbcontext-has-been-disposed-using) – Alper Tunga Arslan Jan 15 '16 at 09:26
Richa - Please check the update. @AlperTungaArslan - Thanks for the link. – Rahul Singh Jan 15 '16 at 09:41

Select one item from each category on the basis of cost

1 Answers1