How to fix the error when only some data is displayed using web API on Xamarin Android - sql-server

Question

I created a personal info page to display all the data according to specific username entered. Unfortunately, the edit text didn't display all the data from the SQL Server. It only shows 2/8 data. I'm using a WEB API to retrieve the data and the data is stored in SQL Server. Can you help me to fix this problem please!!
I obtained this code from a website and i follow step by step according to the website. I've tried using Web services, it didn't work ass well.
VehicleRecord.cs
public class VehicleRecord
{
public string clFullName{ get; set; }
public string clGender{ get; set; }
public string clICNo { get; set; }
public string clAddress { get; set; }
public string clPhoneNo { get; set; }
public string clEmail { get; set; }
public string clUsername { get; set; }
public string clPwd { get; set; }
public string clVehicPlateNo { get; set; }
public string clVehicModel { get; set; }
public string clVehicCol { get; set; }
public string clPaymentMethod { get; set; }
public VehicleRecord()
{
this.clFullName = "";
this.clGender = "";
this.clICNo = "";
this.clAddress = "";
this.clPhoneNo = "";
this.clEmail = "";
this.clUsername = "";
this.clPwd = "";
this.clVehicPlateNo = "";
this.clVehicModel = "";
this.clVehicCol = "";
this.clPaymentMethod = "";
}
}
Service.cs
public class Service
{
public static async Task<dynamic> getServiceData(string queryString)
{
dynamic acc = null;
HttpClient client = new HttpClient();
var response = await client.GetAsync(queryString);
if(response != null)
{
string json = response.Content.ReadAsStringAsync().Result;
acc = JsonConvert.DeserializeObject(json);
}
return acc;
}
}
Acc.cs
public class Acc
{
public static async Task<VehicleRecord> GetAcc(string username)
{
string queryString = "http://xxx.xxx.x.xxx/PMSAPI1/api/users/" + username;
dynamic results = await Service.getServiceData(queryString).ConfigureAwait(false);
if(results != null)
{
VehicleRecord vehicleRecord = new VehicleRecord();
vehicleRecord.clFullName = (string)results["clFullName"];
vehicleRecord.clGender = (string)results["clGender"];
vehicleRecord.clICNo = (string)results["clICNo"];
vehicleRecord.clAddress = (string)results["clAddress"];
vehicleRecord.clPhoneNo = (string)results["clPhoneNo"];
vehicleRecord.clEmail = (string)results["clEmail"];
vehicleRecord.clPwd = (string)results["clPwd"];
vehicleRecord.clVehicPlateNo = (string)results["clVehicPlateNo"];
vehicleRecord.clVehicModel = (string)results["clVehicModel"];
vehicleRecord.clVehicCol = (string)results["clVehicCol"];
vehicleRecord.clPaymentMethod = (string)results["clPaymentMethod"];
return vehicleRecord;
}
else
{
return null;
}
}
}
PersonalInfoActivity.cs
private async void BtnGetAcc_Click(object sender, EventArgs e)
{
EditText username = FindViewById<EditText>(Resource.Id.txtUsername);
if (!String.IsNullOrEmpty(username.Text))
{
VehicleRecord vehicleRecord = await Acc.GetAcc(username.Text);
FindViewById<EditText>(Resource.Id.txtFullName).Text = vehicleRecord.clFullName;
FindViewById<EditText>(Resource.Id.txtGender).Text = vehicleRecord.clGender;
FindViewById<EditText>(Resource.Id.txtIC).Text = vehicleRecord.clICNo;
FindViewById<EditText>(Resource.Id.txtAddress).Text = vehicleRecord.clAddress;
FindViewById<EditText>(Resource.Id.txtPhoneNo).Text = vehicleRecord.clPhoneNo;
FindViewById<EditText>(Resource.Id.txtEmail).Text = vehicleRecord.clEmail;
FindViewById<EditText>(Resource.Id.txtPwd).Text = vehicleRecord.clPwd;
FindViewById<EditText>(Resource.Id.txtPayMethod).Text = vehicleRecord.clPaymentMethod;
}
}
The expected output should display all the data according to the username entered, but the actual output only displayed 2/8 data.
The error that i get is System.NullReferenceException:Object reference not set to an instance of an object.
The output displayed on screen

Answer 1

It seems to me that the issue starts at this line
vehicleRecord.clICNo = (string)results["clICNo"];
IMO results does not contains "clICNo". Check this by surrounding this line in try - catch block.