属性或字段“ ListItemCollectionPosition”尚未初始化尚未请求或尚未执行请求

如何解决属性或字段“ ListItemCollectionPosition”尚未初始化尚未请求或尚未执行请求

我正在尝试通过asp.net获取“共享点”列表项，获取“属性或字段'ListItemCollectionPosition'尚未初始化。尚未请求或未执行请求。可能需要显式请求发生错误。友善的建议。

string repliedBySP = string.Empty;
try
{                    
    ClientContext context = new ClientContext(SharePointSiteURL);
    List list = context.Web.Lists.GetByTitle("APACFLMCCountryCityList");
    context.Load(list); 
    context.Load(list.Fields,c => c.Where(e => e.Hidden != true));
    context.ExecuteQueryAsync();

    ListItemCollectionPosition position = null;
    do
    {
        CamlQuery query = CamlQuery.CreateallItemsQuery(5000);
        query.ListItemCollectionPosition = position;
        ListItemCollection items = list.GetItems(query);
        context.Load(items);
        context.ExecuteQueryAsync();
        position = items.ListItemCollectionPosition;
        string fullItems = string.Empty;
        foreach (ListItem item in items)
        {
            string url = SharePointSiteURL + item["Add_Country"].ToString();
            fullItems += "<a href='" + url + "'>" + item["Title"].ToString() + "</a>" + "<br>";

         }
     } while (position != null);

 }
 catch (Exception ex)
 {
     Console.WriteLine(ex.Message);
 }
 return repliedBySP;