Untitled

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace redditTest
{

    public partial class Students : System.Web.UI.Page
    {


        public List<Student> testList = new List<Student>()
        {
            new Student("Steve", 5),
            new Student("Steve", 2),
            new Student("Steve", 4),
            new Student("Steve", 1),
            new Student("Steve", 5),

        };
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        protected void Button1_Click(object sender, EventArgs e)
        {
            GridView1.DataSource = testList;
            GridView1.DataBind();
        }

        protected void Button2_Click(object sender, EventArgs e)
        {
            //LINQ way
            var goodStudent = from c in testList
                              where c.studentGrade <= 4
                              select c;
            goodStudent.ToList();

            GridView1.DataSource = goodStudent;
            //GridView1.DataSource = goodList;
            GridView1.DataBind();


        }

        protected void Button3_Click(object sender, EventArgs e)
        {
            List<Student> badList = new List<Student>();
            foreach(Student s in testList)
            {
                if (s.studentGrade <= 4)
                {
                    badList.Add(s);
                }
            }
            GridView1.DataSource = badList;
            GridView1.DataBind();
        }
    }
    public class Student
    {
        public string studentName { get; set; }
        public int studentGrade { get; set; }

        public Student(string name, int grade)
        {
            studentName = name;
            studentGrade = grade;
        }


    }
}

//aspx
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Students.aspx.cs" Inherits="redditTest.Students" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:Button ID="Button1" runat="server" Text="Show All Students" OnClick="Button1_Click" />

        <asp:Button ID="Button2" runat="server" Text="Show Top Performers" OnClick="Button2_Click" />

        <asp:Button ID="Button3" runat="server" Text="Show Dunces" OnClick="Button3_Click" />

        <asp:GridView ID="GridView1" runat="server">
        </asp:GridView>
    </div>

    </form>
</body>
</html>