Question

This is not the first time I have been stuck on collections. I’m missing something here and feeling not just a little frustrated. This code snippet is designed return the count of the number of ‘restaurant reviews’ in the REVIEW db that have a specified ‘restaurant id.’ Again I’m getting the a “cannot implicitly covert type” error.

Thanks in advance!

    public IEnumerable<string> getNumReviews(int RestID)
    {
        var NumReviews = from REVIEW in db.REVIEWs
                         where REVIEW.REST_ID == RestID
                         group REVIEW by REVIEW.REVIEW_ID into t
                         select new { REVIEW_ID = t.Key, TagCount = t.Count() };
        return NumReviews;
    }

Answer 1

NumReviews is an IEnumerable<anonymous type>, not an IEnumerable<string>. In particular, you’re returing an enumeration of objects that include a REVIEW_ID and a count of the tags for each review.

Your best option is to declare a type to encapsulate that information:

public class NumReviewInfo
{
    public int ReviewId { get; set; }
    public int NumTags { get; set; }
}

Then, select that object from the method:

public IEnumerable<NumReviewsInfo> getNumReviews(int RestID)
{
    var NumReviews = from REVIEW in db.REVIEWs
                     where REVIEW.REST_ID == RestID
                     group REVIEW by REVIEW.REVIEW_ID into t
                     select new NumReviewsInfo { ReviewId = t.Key, NumTags = t.Count() };
    return NumReviews;
}