public void SortItemName(int itemorder)
 {
     if (itemorder == 0)
     {
         List <Item> spr = new List <Item>();
         for (int i = 0; i < ShowingList.Count; i++)
         {
             spr.Add(ShowingList[i]);
         }
         spr.Sort((x, y) => string.Compare(x.itemNumber, y.itemNumber));
         ShowingList.Clear();
         for (int i = 0; i < spr.Count; i++)
         {
             ShowingList.Add(spr[i]);
         }
         itemOrder = 1;
     }
     else if (itemorder == 1)
     {
         List <Item> spr = new List <Item>();
         for (int i = 0; i < ShowingList.Count; i++)
         {
             spr.Add(ShowingList[i]);
         }
         spr.Sort((y, x) => string.Compare(x.itemNumber, y.itemNumber));
         ShowingList.Clear();
         for (int i = 0; i < spr.Count; i++)
         {
             ShowingList.Add(spr[i]);
         }
         itemOrder = 0;
     }
 }
 public void SortSL(int order)
 {
     if (order == 0)
     {
         List <Item> spr = new List <Item>();
         for (int i = 0; i < ShowingList.Count; i++)
         {
             spr.Add(ShowingList[i]);
         }
         spr = spr.OrderByDescending(o => o.SL).ToList();
         ShowingList.Clear();
         for (int i = 0; i < spr.Count; i++)
         {
             ShowingList.Add(spr[i]);
         }
         slOrder = 1;
     }
     else if (order == 1)
     {
         List <Item> spr = new List <Item>();
         for (int i = 0; i < ShowingList.Count; i++)
         {
             spr.Add(ShowingList[i]);
         }
         spr = spr.OrderBy(o => o.SL).ToList();
         ShowingList.Clear();
         for (int i = 0; i < spr.Count; i++)
         {
             ShowingList.Add(spr[i]);
         }
         slOrder = 0;
     }
 }