Question

public ActionResult Create(FormCollection collection, FormCollection formValue)
{
    try
    {
        Project project = new Project();

        TryUpdateModel(project, _updateableFields);

        var devices = collection["devices"];
        string[] arr1 = ((string)devices).Split(',');
        int[] arr2 = Array.ConvertAll(arr1, s => int.Parse(s));

        project.User = SessionVariables.AuthenticatedUser;
        var time = formValue["Date"];
        project.Date = time;
        project.SaveAndFlush();

        foreach (int i in arr2)
        {
            Device d = Device.Find(i);
            d.Projects.Add(project);
            d.SaveAndFlush();
        }

        return RedirectToAction("Index");
    }
    catch (Exception e)
    {
        return View(e);
    }
}

I want to wrap the foreach in a if statement which checks if

var devices = collection["devices"];

is empty or not. If its empty the for each should not be executed. For the record, collection[“devices”] is a collection of checkbox values from a form.

Answer 1

You do not need to check if the collection is empty, if it is empty the code inside the ForEach will not be executed, see my example below.

using System;
using System.Collections.Generic;

namespace Test
{
    class Program
    {
        static void Main(string[] args)
        {
            List<string> emptyList = new List<string>();

            foreach (string item in emptyList)
            {
                Console.WriteLine("This will not be printed");
            }

            List<string> list = new List<string>();

            list.Add("item 1");
            list.Add("item 2");

            foreach (string item in list)
            {
                Console.WriteLine(item);
            }

            Console.ReadLine();
        }
    }
}