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C# foreach

last modified March 15, 2021

C# foreach tutorial shows how to loop over data in C# with foreach statement and forEach method. C# tutorial is a comprehensive tutorial on C# language.

foreach (var val in vals)
{
    ...
}

The foreach statement executes a statement or a block of statements for each element in a collection which implements IEnumerable.

public void ForEach (Action<T> action);

The ForEach method performs the specified action on each element of the List<T>.

C# foreach array

In the following example, we go over elements of an array using the foreach statement.

Program.cs
using System;

int[] vals = {1, 2, 3, 4, 5};

foreach (var val in vals)
{
    Console.WriteLine(val);
}

The example prints all elements of the array of integers.

$ dotnet run
1
2
3
4
5

C# foreach List

In the following example, we loop over a list with the foreach statement.

Program.cs
using System;
using System.Collections.Generic;

var words = new List<string> {"tea", "falcon", "book", "sky"};

foreach (var word in words)
{
    Console.WriteLine(word);
}

We print all elements of the list of strings.

$ dotnet run
tea
falcon
book
sky

C# foreach Dictionary

The following example loops over elements of a dictionary with foreach statement.

Program.cs
using System;
using System.Collections.Generic;

var domains = new Dictionary<string, string>
{ 
    {"sk", "Slovakia"}, 
    {"ru", "Russia"},
    {"de", "Germany"},
    {"no", "Norway"}
};

foreach (var pair in domains)
{
    Console.WriteLine($"{pair.Key} - {pair.Value}");
}

Console.WriteLine("-----------------------");

foreach ((var Key, var Value) in domains) 
{
    Console.WriteLine($"{Key} - {Value}");
}

We have a dictionary of domains. Using the foreach statement, we loop over the key/value pairs of the dictionary.

$ dotnet run
sk - Slovakia
ru - Russia
de - Germany
no - Norway
-----------------------
sk - Slovakia
ru - Russia
de - Germany
no - Norway

C# forEach array

In the following example, we go over elements of an array using the forEach method.

Program.cs
using System;

int[] vals = {1, 2, 3, 4, 5};

Array.ForEach(vals, e => Console.WriteLine(e));

The example prints all elements of the array of integers. We use the Array.ForEach method.

C# forEach List

In the following example, we loop over a list with the forEach method.

Program.cs
using System;
using System.Collections.Generic;

var words = new List<string> {"tea", "falcon", "book", "sky"};

words.ForEach(e => Console.WriteLine(e));

We print all elements of the list of strings.

C# foreach Dictionary

The following example loops over elements of a dictionary with ForEach. In this case we also use Linq.

Program.cs
using System;
using System.Collections.Generic;
using System.Linq;

var domains = new Dictionary<string, string>
{ 
    {"sk", "Slovakia"}, 
    {"ru", "Russia"},
    {"de", "Germany"},
    {"no", "Norway"}
};

domains.ToList().ForEach(pair => Console.WriteLine($"{pair.Key} - {pair.Value}"));

We call Linq's ToList method to transform the dictionary to a list and then call the ForEach method.

In this tutorial we have covered the foreach statement and the forEach method in C#.

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