How to read site page contents in SharePoint using CSOM?

 var listTitle = "Site Pages";

var list = ctx.Web.Lists.GetByTitle(listTitle);

var items = list.GetItems(CamlQuery.CreateAllItemsQuery());

ctx.Load(items, icol => icol.Include( i => i["WikiField"], i => i["Roaf"], i => i["FileRef"], i => i.ContentType));

ctx.ExecuteQuery();

foreach (var item in items)

{

     Console.WriteLine(">>> {0}", item["FileRef"]);

     switch (item.ContentType.Name)

     {

        case "Site Page":

          Console.WriteLine(item["Roaf"]);

          break;

        case "Wiki Page":

          Console.WriteLine(item["WikiField"]);

          break;

     }    

 }