Listing tasks
Learn to print tasks formatted with ListTasks.
Listing tasks
After adding tasks to the list, we want to see them. The ListTasks method walks through all tasks with foreach and prints each one's Title to the screen.
The method signature: static void ListTasks(List<Task> tasks). The body is the loop foreach (Task t in tasks) { Console.WriteLine(t.Title); }. This structure iterates the list from start to end.
Iterating with foreach
The foreach loop walks through all elements of a collection in order. foreach (Task t in tasks) assigns each task to the variable t and runs the loop body.
This removes the risk of an indexing mistake; you do not have to manage an index variable i as in a for loop. It is ideal for a one-way pass over a list.
Exercise ListTasks method
Write the body of ListTasks: foreach (Task t in tasks) { Console.WriteLine(t.Title); }. In Main, add two tasks (AddTask(tasks, "Buy bread") and AddTask(tasks, "Buy milk")) then call ListTasks(tasks).
Show example solution
Add foreach (Task t in tasks) { Console.WriteLine(t.Title); } to the ListTasks body, write ListTasks(tasks); in Main.
Example solution:
using System;
using System.Collections.Generic;
class Task
{
public string Title;
public bool IsDone;
}
class Program
{
static void AddTask(List<Task> tasks, string title)
{
tasks.Add(new Task { Title = title, IsDone = false });
}
static void ListTasks(List<Task> tasks)
{
// Print each task's title with foreach
foreach (Task t in tasks)
{
Console.WriteLine(t.Title);
}
}
static void Main()
{
List<Task> tasks = new List<Task>();
AddTask(tasks, "Buy bread");
AddTask(tasks, "Buy milk");
// Add a ListTasks call
ListTasks(tasks);
}
}Test yourself
-
What does tasks[0].Title print?
List<Task> tasks = new List<Task>(); tasks.Add(new Task { Title = "Buy bread", IsDone = false }); tasks.Add(new Task { Title = "Buy milk", IsDone = false }); Console.WriteLine(tasks[0].Title);- Buy milk
- Buy bread
- Empty
- 2
Show answer
Buy bread — Correct. The first added task has index 0; its Title is "Buy bread".
-
foreach loop
foreach (____) { Console.WriteLine(t.Title); }Show answer
foreach (Task t in tasks) { Console.WriteLine(t.Title); } -
Match each expression to its meaning
- foreach
- Iterate each
- t.Title
- Task title
- Console.WriteLine
- tasks.Count
- Total tasks