无法在C＃中找出IQueryable

Question

This is my class:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
{
    public class Attendee
    {
        public int AttendeeId { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
    }
}

Later in the code I am trying to use that class but it is declared as IEnumerable :

IQueryable<Attendee> myList;

I need to able to manually populate it. Something like this:

IQueryable<Attendee> districtList = new IQueryable<Attendee>() { AtendeeId = 1, FirstName = "First Name", LastName = "Last Name" }; <- This does not work. I need example of how to add one item or more then one item.

I would really appreciate an example of how to populate it with some fake data manually like "Test String", "test ID" etc. myList is just a variable.

To fix it I did the following:

var attendees = new List<Attendee>();
// Manually Populate Attendees list

myList = attendees.AsQueriable();

Answer 1

IQueryable<T> is an interface, so you can't instantiate it directly. Instead, you need to create an instance of a class that implements the interface. For example:

List<string> myList = new List<string>(){"foo", "bar"};
IQueryable<string> myQueryable = myList.AsQueryable();

Note: In this example, I'm using the LINQ AsQueryable() method to convert from an IEnumerable<T> (ie List<T> ) to an IQueryable<T> .