current community

your communities

more stack exchange communities

company blog
Stack Exchange Inbox Reputation and Badges
tour help
Code Review Stack Exchange is a question and answer site for peer programmer code reviews. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top
up vote 9 down vote favorite
2

Is there any way to refactor this?

public IEnumerable<Option> Options
{
    get
    {
        {
            List<Option> ListOption = new List<Option>();

            if (!String.IsNullOrEmpty(Option1)) 
            {
                ListOption.Add(new Option() {Name=Option1 });
            }
            if (!String.IsNullOrEmpty(Option2))
            {
                ListOption.Add(new Option() { Name = Option2 });
            }
            if (!String.IsNullOrEmpty(Option3))
            {
                ListOption.Add(new Option() { Name = Option3 });
            }
            if (!String.IsNullOrEmpty(Option4))
            {
                ListOption.Add(new Option() { Name = Option4 });
            } 

            return ListOption;
        }
    }
}

public class Option
{
    public string Name { get; set; }
}
share|improve this question
up vote 26 down vote accepted

This is a bit neater:

List<Option> ListOption = new List<Option> { };
Action<string> add = x => { if (!String.IsNullOrEmpty(x)) ListOption.Add(new Option { Name = x }); }
add(Option1);
add(Option2);
add(Option3);
add(Option4);
return ListOption;

This is perhaps even better:

return (new string[] {Option1, Option2, Option3, Option4})
       .Where(x => !String.IsNullOrEmpty(x))
       .Select(x => new Option { Name = x })
       .ToList();
share|improve this answer
up vote 7 down vote

This is a good opportunity to use the yield operator:

public IEnumerable<Option> Options
{
    get
    {
        if (!string.IsNullOrEmpty(Option1)) yield return new Option{Name=Option1};
        if (!string.IsNullOrEmpty(Option2)) yield return new Option{Name=Option2};
        if (!string.IsNullOrEmpty(Option3)) yield return new Option{Name=Option3};
        if (!string.IsNullOrEmpty(Option4)) yield return new Option{Name=Option4};
    }
}
share|improve this answer
up vote 5 down vote

Just to be kind of outrageous, here's a version using a standard looping mechanism:

static List<Option> GetNonNullOptions(params string[] options)
{
    var results = new List<Option>();
    if (options != null)
    {
        foreach (var option in options)
        {
            if (option != null)
            {
                results.Add(new Option { Name = option });
            }
        }
    }
    return results;
}

Leaving you to do something like this:

var nonNullOptions = GetNonNullOptions(Option1, Option2, Option3, Option4);

Notice that I only check for null value items, as an empty string and a null value are two different things.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.