public async Task <bool> AddItemAsync(SiteAnnouncement data)
 {
     if (!Usable)
     {
         return(false);
     }
     return(await DataProvider.AddAsync(data));
 }
 public async Task <UpdateStatusEnum> UpdateItemAsync(SiteAnnouncement data)
 {
     return(await DataProvider.UpdateByIdentityAsync(data.Key, data));
 }