Take and Skip

Learn slicing with Take, Skip, TakeWhile and SkipWhile.

Slicing with Take and Skip

Take(n) takes the first n elements of a collection. Skip(n) skips the first n and returns the rest. Both are deferred; the result is again an IEnumerable<T>.

For pagination you combine them: 5 items on page 2 is items.Skip(5).Take(5). This pattern also shows up in database queries. Taking more than available is safe; Take returns what it has.

TakeWhile and SkipWhile

TakeWhile(condition) takes elements from the start as long as the condition holds; it stops at the first mismatch. SkipWhile(condition) skips from the start as long as the condition holds; it returns everything from the first mismatch onward.

Example: new[] { 2, 4, 6, 7, 8 }.TakeWhile(n => n % 2 == 0) yields { 2, 4, 6 }; 7 is odd, so it stops. These methods are useful for finding patterns in ordered data.

Exercise Take the first three

Take the first three elements of numbers with Take(3) and print each in a foreach loop.

Show example solution

Take the first three with numbers.Take(3), loop with foreach, print with Console.WriteLine(n).
Example solution:
using System;
using System.Linq;

class Program
{
    static void Main()
    {
        int[] numbers = { 10, 20, 30, 40, 50 };
        foreach (var n in numbers.Take(3))
        {
            Console.WriteLine(n);
        }
    }
}

Test yourself

How is pagination done?
- Take(5).Skip(5)
- Skip(5).Take(5)
- Skip(5).Distinct()
- Take(5).Where(...)
Show answer

Skip(5).Take(5) — Correct. First Skip past the earlier pages, then Take the items of the target page.
Match each method to its result

Take(3)

First three
Skip(3)

Skip first three
TakeWhile(...)

Until break
SkipWhile(...)

After break

Complete the Take call

var first3 = numbers.____(3);

Show answer

var first3 = numbers.Take(3);

Next lesson: ToDictionary

We Are Enhancing Your Experience

Cookie Preferences

Strictly Necessary Cookies

Analytical Cookies