Multidimensional Lists in C#

Question

At the moment I am using one list to store one part of my data, and it's working perfectly in this format:

Item
----------------
Joe Bloggs
George Forman
Peter Pan

Now, I would like to add another line to this list, for it to work like so:

NAME                    EMAIL
------------------------------------------------------
Joe Bloggs              [email protected]
George Forman           [email protected]
Peter Pan               [email protected]

I've tried using this code to create a list within a list, and this code is used in another method in a foreach loop:

// Where List is instantiated
List<List<string>> list2d = new List<List<string>>

...

// Where DataGrid instance is given the list
dg.DataSource = list2d;
dg.DataBind();

...


// In another method, where all people add their names and emails, then are added
// to the two-dimensional list
foreach (People p in ppl.results) {
    list.Add(results.name);
    list.Add(results.email);
    list2d.Add(list);
}

When I run this, I get this result:

Capacity Count 
----------------
16       16 
16       16 
16       16
...      ...

Where am I going wrong here. How can I get the output I desire with the code I am using right now?

Answer 1

Why don't you use a List<People> instead of a List<List<string>> ?

Answer 2

Highly recommend something more like this:

public class Person {
    public string Name {get; set;}
    public string Email {get; set;}
}

var people = new List<Person>();

Easier to read, easy to code.

Answer 3

If for some reason you don't want to define a Person class and use List<Person> as advised, you can use a tuple, such as (C# 7):

var people = new List<(string Name, string Email)>
{
  ("Joe Bloggs", "[email protected]"),
  ("George Forman", "[email protected]"),
  ("Peter Pan", "[email protected]")
};

var georgeEmail = people[1].Email;

The Name and Email member names are optional, you can omit them and access them using Item1 and Item2 respectively.

There are defined tuples for up to 8 members.

For earlier versions of C#, you can still use a List<Tuple<string, string>> (or preferably ValueTuple using this NuGet package), but you won't benefit from customized member names.