Get values from multichoice column client object model sharepoint 2010

A short code snippet about how to add and retrieve values from multichoice column using client object model.

ListItemCollection listItems = list.GetItems(camlQuery);

//Add values -

listItems[0]["MultiChoiceField"] = newstring[] {"Choice 1″,"Choice 4″ };

//Retrieve -

  if (listItems[0]["testmultichoice"] != null)
      {
        string[] values = listItems[0]["testmultichoice"] as string[];

        if (values != null)
        {
          var result = from c in values where c.Contains(searchChoice) select c;
          if (result != null)
            choices = result.ToList();
        }

      }
      return choices;