private void BuySet_Changed(BuySet set)
 {
     if (this.Changed != null)
     {
         this.Changed(this);
     }
     return;
 }
 /// <summary>
 /// Check for an existing buy set
 /// </summary>
 /// <param name="set">Buy set to check for</param>
 /// <returns>True if the buy set is already present, false otherwise</returns>
 public bool Contains(BuySet set)
 {
     if (set == null)
     {
         throw new ArgumentNullException("set", "You must provide a valid BuySet");
     }
     return(this.BuySets.Contains(set));
 }
 /// <summary>
 /// Remove the specified buy set
 /// </summary>
 /// <param name="set">Buy set to remove</param>
 public void Remove(BuySet set)
 {
     if (set == null)
     {
         throw new ArgumentNullException("set", "You must provide a valid BuySet");
     }
     set.Changed -= this.BuySet_Changed;
     this.BuySets.Remove(set);
     if (this.Changed != null)
     {
         this.Changed(this);
     }
     return;
 }