how can i add these 3 records to SortedList
                            
                         
                        
                     
                 
                
                    using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
namespace SortedListDemo 
{ 
class Sorted_List 
{ 
int id, marks; 
string name; 
public Sorted_List(int id, string name, int marks) 
{ 
this.id = id; 
this.name = name; 
this.marks = marks; 
} 
public override string ToString() 
{ 
return String.Format("id: {0,-5} name: {1,-5} marks : { 2}",id,name,marks); 
} 
} 
class SortedList1 
{ 
static void Main(string[] args) 
{ 
SortedList<Sorted_List, int> sobj = new SortedList<Sorted_List, int>(); 
Sorted_List s = new Sorted_List(1, "hello", 34); 
Sorted_List s1 = new Sorted_List(20, "world", 32); 
Sorted_List s2 = new Sorted_List(0, "hai", 98); 
//here not adding the records,giving string format exception 
sobj.Add(s, 3); 
sobj.Add(s1, 0); 
sobj.Add(s2, 1); 
foreach (KeyValuePair<Sorted_List, int> s4 in sobj) 
{ 
Console.WriteLine(s4); 
} 
} 
}