Access implicitly typed variable outside the block

Question

Im trying to declare a variable as an object which returns an anonymous type object. I get an error like (cannot implicitly convert type Anonymous1 to Anonymous2.

var queryResult = new object();

            if (check == 1)
            {
                queryResult = context.SubjectContext
                    .Where(x => x.CreatedBy == CreatedBy)
                    .Select(x => new { x.Id, x.Name });
            }
            else (check == 2)
            {
                queryResult = context.SubjectContext
                    .Where(x => x.CreatedBy == CreatedBy)
                    .Select(x => new { x.Id, x.Name, x.Skillset });
            }


            if (queryResult.Any())
            {
                return jsonRetrunMsg = new JsonReturn { Status = "success", Message = queryResult };
            }
            else
            {
                return jsonErrorMsg = new JsonError { Status = "error", Message = "Check User Id" };
            }

Answer 1

Although you are selecting from the same context, in this case 'SubjectContext', you are creating a new type, when doing this:

.Select(x => new { x.Id, x.Name });

and this;

.Select(x => new { x.Id, x.Name, x.Skillset });

So, in this case, you have to return to an implicity-typed variable, known as 'var'. Something like this:

var queryResult = context.SubjectContext
        .Where(x => x.CreatedBy == CreatedBy)
        .Select(x => new { x.Id, x.Name });

Of course, in this case - which you are using it between the brackets -, you have to change the declaration of the 'queryResult', and control the result, before returning. Something like this:

   if (check == 1)
   {
        var queryResult = context.SubjectContext
            .Where(x => x.CreatedBy == CreatedBy)
            .Select(x => new { x.Id, x.Name });

        if (queryResult.Any())
        {
            return jsonRetrunMsg = new JsonReturn { Status = "success", Message = queryResult };
        }
        else
        {
            return jsonErrorMsg = new JsonError { Status = "error", Message = "Check User Id" };
        }

    } else if (check == 0)
    {
        var queryResult = context.SubjectContext
            .Where(x => x.CreatedBy == CreatedBy)
            .Select(x => new { x.Id, x.Name, x.Skillset });

        if (queryResult.Any())
        {
            return jsonRetrunMsg = new JsonReturn { Status = "success", Message = queryResult };
        }
        else
        {
            return jsonErrorMsg = new JsonError { Status = "error", Message = "Check User Id" };
        }
    }

In this case, the var queryResult will assume the type of the returned/created type in your Linq Query, and the error will not occour.

Well, reading the comments, i came to another solution for you, i guess it'll work, just give it a shot.

using System.Collections;
object queryResult;
        if (check == 1)
        {
            queryResult = context.SubjectContext
                .Where(x => x.CreatedBy == CreatedBy)
                .Select(x => new { x.Id, x.Name });

        } else if (check == 0)
        {
            queryResult = context.SubjectContext
                .Where(x => x.CreatedBy == CreatedBy)
                .Select(x => new { x.Id, x.Name, x.Skillset });
        }

        if ((queryResult != null) && ((queryResult as ICollection).Count > 0))
        {
            return jsonRetrunMsg = new JsonReturn { Status = "success", Message = queryResult };
        }
        else
        {
            return jsonErrorMsg = new JsonError { Status = "error", Message = "Check User Id" };
        }

Guess you can think about something to avoid this lot of code, but, it'll works for now. Victor.

Answer 2

I would recommend you create a class since they have similarities on field

public class Student
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string Skillset { get; set; }
}

and your code will be like this.

object queryResult;

if (check == 1)
{
    queryResult = context.SubjectContext
        .Where(x => x.CreatedBy == CreatedBy)
        .Select(x => new Student() { Id = x.Id, Name = x.Name });
}
else (check == 2)
{
    queryResult = context.SubjectContext
        .Where(x => x.CreatedBy == CreatedBy)
        .Select(x => new Student() { Id = x.Id, Name = x.Name, Skillset = x.Skillset });
}

if (queryResult.Any())
{
    return jsonRetrunMsg = new JsonReturn { Status = "success", Message = queryResult };
}
else
{
    return jsonErrorMsg = new JsonError { Status = "error", Message = "Check User Id" };
}