Lists and foreach

8 min 20 XP + 10 for no hints

A List holds many values of one type and can grow. Add using System.Collections.Generic;, then create one: List<string> names = new List<string>();

names.Add("Asha"); adds an item, and names.Count tells you how many there are.

foreach visits every item in order: foreach (string n in names) { … }. Open Step through to watch it work.

Example (inside Main)

List<int> scores = new List<int> { 7, 9 };
scores.Add(10);
Console.WriteLine(scores.Count);

Output

Lists use Count; arrays use Length. Mixing them up is a common error.

Your tasks

0 of 3 done

Create a List<string> called fruits
Add three fruits with fruits.Add()
Print each fruit with foreach

Quick check

How do you get the number of items in a List?

Program.csChecked as you type

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        // 1. Create a List<string> called fruits

        // 2. Add three fruits with Add()

        // 3. Print each fruit with foreach

    }
}

No problems found. Unclosed tags, missing semicolons and errors show up here in plain words.

1using System;

2using System.Collections.Generic;

4class Program

6 static void Main()

7 {

8 List<string> pets = new List<string>();

9 pets.Add("cat");

10 pets.Add("dog");

11 foreach (string p in pets)

12 {

13 Console.WriteLine(p);

14 }

15 Console.WriteLine($"Total: {pets.Count}");

16 }

17}

An empty list called pets is created.

Variables

pets

[ ]

Output

Step 1 of 9

Lists and foreach

Your tasks

Tutor

Quick check

Variables

Output