The foreach loop in C# executes a block of code on each element in an array or a collection of items. When executing foreach loop it traversing items in a collection or an array . The foreach loop is useful for traversing each items in an array or a collection of items and displayed one by one.

  foreach(variable type in collection){

    // code block
  }

  variable type : The variable used for collect the item from Collection

  collection	  : Collection of items

  string[] days = { "Sunday", "Monday", "TuesDay"};
  foreach (string day in days)
  {
	  MessageBox.Show("The day is : " + day);
  }

The above C# example first declared a string array 'days' and initialize the days in a week to that array. In the foreach loop declare a string 'day' and pull out the values from the array one by one and displayed it.

using System;
using System.Windows.Forms;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string[] days = { "Sunday", "Monday", "TuesDay", "Wednesday", "Thursday", "Friday", "Saturday" };
            foreach (string day in days)
            {
                MessageBox.Show("The day is : " + day);
            }
        }
    }
}