Question

I have a problem with c# List, not sure where I’m missing the point while adding a new object to the Managepagesid List!

 public class Clients
    {
        [BsonId]
        public string Id { get; set; } //Object ID managed by MongoDb

        public string Name { get; set; } //Client Name

        public string Phone { get; set; } //Client Phone

        public string Email { get; set; } //Client E-mail

        public string Username { get; set; } //Client Username

        public DateTime LastModified { get; set; } //Client Last Login

        public string FB_User_Id { get; set; } //Client FB User ID

        public AccessToken UserAccessToken { get; set; } //AccessToken which is stored while user is logged in.

        public List<ManagePages> Manage_Pages_id { get; set; } //The pages maintained by the specific client
     }

---

I’m trying to access add a new item into ManagePage_id list but its thrwing some null exception.. Help!

Clients client = new Clients();

            client.FB_User_Id = FBData.id;
            client.Name = FBData.name;
            client.Email = FBData.email;
            client.Username = FBData.username;

            for (int index = 0; index < FBData.accounts["data"].Count; index++)
            {
                ManagePages pagedetails = new ManagePages()
                {
                    page_id = FBData.accounts["data"][index].id,
                    page_name = FBData.accounts["data"][index].name,
                    ManagePages_AccessTokens = new AccessToken()
                    {
                        AccessToken_accessToken = FBData.accounts["data"][index].access_token,
                        AccessToken_expiryDate = DateTime.Now
                    },
                    ManagePages_category = FBData.accounts["data"][index].category
                };

                var category = pagedetails.ManagePages_category;

                client.Manage_Pages_id.Add(pagedetails);
            }

Stack Trace added!

Exception>System.NullReferenceExceptionObject reference not set to an instance of an object. at Vega_MongoDB.FBDataAccess.ClientFBRepository.ClientsData(String accessToken) in g:\Development\Vega_MongoDB\Vega_MongoDB\FBDataAccess\ClientFBRepository.cs:line 48
at Vega_MongoDB.Models.ClientRepository..ctor(String connection) in g:\Development\Vega_MongoDB\Vega_MongoDB\Models\Clients\ClientRepository.cs:line 47
at Vega_MongoDB.Models.ClientRepository..ctor() in g:\Development\Vega_MongoDB\Vega_MongoDB\Models\Clients\ClientRepository.cs:line 23
at Vega_MongoDB.Controllers.ClientsController..cctor() in g:\Development\Vega_MongoDB\Vega_MongoDB\Controllers\ClientsController.cs:line 18

And I have checked the pagedetails object, it contains all the data..

Thanks

Vishnu

Answer 1

Try adding this to your class:

public Clients()
{
  this.Manage_Pages_id = new List<ManagePages>();
}