SqlDataReader result to List

Question

I am trying to pull records from sql server by using SqlDataReader and dump to a List. I am having object reference not set to instance of an object error. Below is the code.

        private List<Models.AreasOfLaw> aolTitles;

    public List<Models.AreasOfLaw> AreasOfLawListItems
    {
        get { return aolTitles; }
        set { aolTitles = value; OnPropertyChanged("AoLTitles"); }
    }

    private void GetAllAreasOfLaws()
    {
        try
        {
            using (SqlConnection sqlConnection = new SqlConnection(DataSources.RemoteConnectionString()))
            {
                sqlConnection.Open();
                string commandText = "SELECT AreaOfLawTitle FROM [dbo].[CLR.AreaOfLaw] ORDER BY AreaOfLawTitle";
                using (SqlCommand sqlCommand = new SqlCommand(commandText, sqlConnection))
                {
                    sqlCommand.CommandType = CommandType.Text;
                    SqlDataReader reader = sqlCommand.ExecuteReader();
                    while (reader.Read())
                    {
                        string aolTitle = Convert.ToString(reader["AreaOfLawTitle"]);


                        AreasOfLawListItems.Add(new Models.AreasOfLaw { AreaOfLawTitle = aolTitle });
                    }
                    int n = AreasOfLawListItems.Count;
                }
                sqlConnection.Close();

            }
        }
        catch (Exception ex)
        {

        }
    }

I am desperate folks. Thank you.

Use the breakpoints int he beginning of the function to see what line throws the exception. — HEWhoDoesn'tKnow, Nov 12 '18 at 09:12
You forgot to initialise `AreasOfLawListItems` / `aolTitles`. — mjwills, Nov 12 '18 at 09:13
the 'AreasOfLawListItems.Add(new Models.AreasOfLaw { AreaOfLawTitile = aolTitle}); — Bainn, Nov 12 '18 at 09:15

score 1 · Answer 1 · edited Nov 12 '18 at 09:27

1

Your list aolTItles is never initiliased.

Your code should look like this

private List<Models.AreasOfLaw> aolTitles = new List<Models.AreasOfLaw>();

public List<Models.AreasOfLaw> AreasOfLawListItems
{
    get { return aolTitles; }
    set { aolTitles = value; OnPropertyChanged("AoLTitles"); }
}

Declaring a variable and intiliasing it are 2 separate steps, and you can't use a variable until you've initialised it.

edited Nov 12 '18 at 09:27

WhatsThePoint

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answered Nov 12 '18 at 09:16

Dave

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1

Thanks for the reminder. It worked. Thank you very much indeed. – Bainn Nov 12 '18 at 09:28

SqlDataReader result to List

1 Answers1