Dictionary

Hi, i am making Inventory system using Dictonaries. When i write my Dictionary definition it is allright, but when i write anything after it, even space, it says "The name "Dictionary" does not exist in current context". I have imported System.Collections.Generic and rest of script is fine. Any idea? Thanks

EDIT: CODE (it is on the very end of it)

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 
 public class InventoryClass {
 
 }
 
 public class Inventory {
     Slot[] inventory;
     
     public Inventory () {
         inventory = new Slot[20];
         createInventory ();
     }
     
     public Inventory (int SlotCount) {
         inventory = new Slot[SlotCount];
         createInventory ();
     }
 
     public Slot[] Inventory2 {
         get {
             return inventory;
         }
     }
 
     void createInventory () {
         for (int slotI = 0; slotI < inventory.Length; slotI++) {
             inventory[slotI] = new Slot(Item.ItemTypes.Stone);
         }
     }
 }
 
 public class Slot {
     
     public enum ChangeItemCountMode {Add, Remove, Set};
     
     int contentCount;
     Item content;
     
     public Slot () {
         content = new Item(Item.ItemTypes.Empty);
         contentCount = 0;
     }
     
     public Slot (Item.ItemTypes itemtype) {
         content = new Item(itemtype);
         contentCount = 1;
     }
     
     public Slot (Item.ItemTypes itemtype, int itemcount) {
         content.ChangeItemType(itemtype);
         contentCount = itemcount;
     }
     
     public void ChangeItemCount (ChangeItemCountMode mode, int number) {
         int oldCount = contentCount;
         if (mode == ChangeItemCountMode.Add) {
             contentCount += number;
         } else if (mode == ChangeItemCountMode.Remove) {
             contentCount -= number;
         } else if (mode == ChangeItemCountMode.Set) {
             contentCount = number;
         }
         content.OnItemCountChanged (oldCount, contentCount);
     }
 
     public Item Content {
         get {
             return content;
         }
     }
 
 }
 
 public class Item {
     public enum ItemTypes {Empty, Dirt, Stone};
     
     ItemTypes itemtype;
     
     public Item () {
         itemtype = ItemTypes.Empty; 
     }
     
     public Item (ItemTypes itemtype_) {
         itemtype = itemtype_;
     }
     
     public void ChangeItemType (ItemTypes itemtype_) {
         itemtype = itemtype_;
     }
     
     public ItemTypes Itemtype {
         get {
             return itemtype;
         }
     }
 
     //Dummy method to override.
     public virtual void OnItemCountChanged (int prevCount, int newCount) {
         
     }
 }
 
 public class ItemList {
     Dictionary<int, string, Sprite> itemDic = new Dictionary<int, string, Sprite>();
 }