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added code for building ienumerable in generic getdata method
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Delfino
Delfino
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EDIT

Here is the code I have for building the IEnumerable inside my GetData method:

public static IEnumerable<TBuilding> GetBuildingData<TBuilding>() 
    where TBuilding : Building, new()
{
    DataTable table;
    string myConnectionString = @"Data Source=(LocalDb)\MSSQLLocalDb;Initial Catalog=Test;Integrated Security=True;";
    List<TBuilding> buildings = new List<TBuilding>();
    using (SqlConnection connection = new SqlConnection(myConnectionString))
    {
        using (SqlCommand command = new SqlCommand("[dbo].[GetListData]", connection) { CommandType = CommandType.StoredProcedure })
        {
            connection.Open();
            using (SqlDataAdapter adapter = new SqlDataAdapter(command))
            {
                table = new DataTable();
                adapter.Fill(table);
            }
            connection.Close();
        }
    }
    foreach (DataRow row in table.Rows)
    {
        TBuilding building = new TBuilding();
        building.Area = Convert.ToDouble(row["Area"]);
        building.Name = row["Name"].ToString();
        building.Stories = Convert.ToInt32(row["Stories"]);
        buildings.Add(building);
    }
    return buildings;
}

EDIT

Here is the code I have for building the IEnumerable inside my GetData method:

public static IEnumerable<TBuilding> GetBuildingData<TBuilding>() 
    where TBuilding : Building, new()
{
    DataTable table;
    string myConnectionString = @"Data Source=(LocalDb)\MSSQLLocalDb;Initial Catalog=Test;Integrated Security=True;";
    List<TBuilding> buildings = new List<TBuilding>();
    using (SqlConnection connection = new SqlConnection(myConnectionString))
    {
        using (SqlCommand command = new SqlCommand("[dbo].[GetListData]", connection) { CommandType = CommandType.StoredProcedure })
        {
            connection.Open();
            using (SqlDataAdapter adapter = new SqlDataAdapter(command))
            {
                table = new DataTable();
                adapter.Fill(table);
            }
            connection.Close();
        }
    }
    foreach (DataRow row in table.Rows)
    {
        TBuilding building = new TBuilding();
        building.Area = Convert.ToDouble(row["Area"]);
        building.Name = row["Name"].ToString();
        building.Stories = Convert.ToInt32(row["Stories"]);
        buildings.Add(building);
    }
    return buildings;
}
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Delfino
Delfino
  • 519
  • 5
  • 13

Creating custom objects with custom properties using generics

I have two base classes: City and Building:

public class City
{
    public string Name { get; set; }
    public double Area { get; set; }
}

public class Building
{
    public string Name { get; set; }
    public double Area { get; set; }
    public int Stories { get; set; }
}

With two classes that inherit from Building, with their own Id property:

public class MyBuilding : Building
{
    public int MyId { get; set; }
}

public class HisBuilding : Building
{
    public int HisId { get; set; }
}

And two classes that inherit from City, with their own Id and IEnumerable<Building> properties:

public class MyCity : City
{
    public int MyId { get; set; }
    public IEnumerable<MyBuilding> Buildings { get; set; }
}

public class HisCity : City
{
    public int HisId { get; set; }
    public IEnumerable<HisBuilding> Buildings { get; set; }
}

Below is a method I've created that returns a KeyValuePair<City, Building> using generics:

public static KeyValuePair<TCity, IEnumerable<TBuilding>> GetData<TCity, TBuilding>()
    where TCity : City, new()
    where TBuilding : Building, new()
{
    TCity city = new TCity();
    IEnumerable<TBuilding> buildings = new List<TBuilding>();
    return new KeyValuePair<TCity, IEnumerable<TBuilding>>(city, buildings);
}

And in my Main method I've logic that instantiates a specific City object based on a user's input.

int input = -1;
string strInput = Console.ReadLine();
int.TryParse(strInput, out input);
string json = string.Empty;
switch (input)
{
    case 1:
        KeyValuePair<MyCity, IEnumerable<MyBuilding>> myCity
            = GetData<MyCity, MyBuilding>();
        MyCity my = myCity.Key;
        my.MyId = 1;
        my.Buildings = myCity.Value;
        json = JsonConvert.SerializeObject(my, Formatting.Indented);
        break;
    
    default:
        KeyValuePair<HisCity, IEnumerable<HisBuilding>> hisCity
            = GetData<HisCity, HisBuilding>();
        HisCity his = hisCity.Key;
        his.HisId = 2;
        his.Buildings = hisCity.Value;
        json = JsonConvert.SerializeObject(his, Formatting.Indented);
        break;
}
Console.WriteLine(json);
Console.ReadLine();

The above generic method is just something I cobbled together in the last half hour, but I'm wondering if there is a more efficient way of creating these custom objects of mine, especially when each City has its own, different IEnumerable<Building> property.