C# Arrays and Lists

An array has a fixed size. A List<T> can grow and shrink, and is used far more often.

ExampleC#

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        int[] nums = { 10, 20, 30 };
        Console.WriteLine(nums[1]);
        Console.WriteLine(nums.Length);

        List<string> cars = new List<string>();
        cars.Add("Volvo");
        cars.Add("BMW");
        cars.Add("Ford");
        cars.Remove("BMW");
        cars.Sort();
        Console.WriteLine(cars.Count);
        Console.WriteLine(string.Join(", ", cars));

        Dictionary<string, int> ages = new Dictionary<string, int>();
        ages["Ada"] = 36;
        ages["Sam"] = 22;
        Console.WriteLine(ages["Ada"]);
        Console.WriteLine(ages.ContainsKey("Lee"));
    }
}

Output

20
3
2
Ford, Volvo
36
False

Quick check

Which type is a resizable list in C#?

List<T>Array<T>Vector

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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