Remove duplicates in multi-element string[] array?

I have a string[] array that is split by \r. Each row in the array has title|address in it, but every so often I end up with a duplicate of the address portion of it, which I don't want.

This:

Title1 | Address1 //[0]
Title2 | Address2 //[1]
Title3 | Address1 //[2]
Title4 | Address3 //[3]

Would become:

Title1 | Address1 //[0]
Title2 | Address2 //[1]
Title4 | Address3 //[2]

The array declaration is as follows: string[] resultsArray = results.Split('\r'); //Title|Address I then later split the row when I grab the individual elements by |.

Usage (extre开发者_如何学Gomely simplified):

foreach (string result in resultsArray)
{
    string splitResult[] = result.Split('|');
    title = splitResult[0];
    address = splitResult[1];
}

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I'm assuming the question is, how do you prevent duplicate addresses from being entered into the list. Could you use a Dictionary?

Dictionary<string, string> addresses = new Dictionary<string, string>();

foreach(string result in resultsArray)
{
    string splitResult[] = result.Split('|');

    // check to see if address already exists, if it does, skip it.
    if(!addresses.ContainsKey(splitResult[1]))
    {
        addresses.add(splitResult[1], splitResult[0]);
    }
}   

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string[] strings = { "Title1 | Address1", "Title2 | Address2", "Title3 | Address1", "Title4 | Address3" };
var _strings = strings.GroupBy(s => s.Split('|')[1]).Select(g => g.Min(s => s));

---

var seenItBefore = new HashSet<string>();
foreach (string result in resultsArray)
{
    string splitResult[] = result.Split('|');
    title = splitResult[0];
    address = splitResult[1];

    if (!seenItBefore.Add(address)) continue;

    // process
}

You could also supply a projecting IEqualityComparer<string[]>to Distinct() if you're building up a vine of IEnumerable<>, but since your sample doesn't use it, I decided to stick with classic procedural.

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Using John Skeet's ProjectionComparer, it becomes rather easy:

var comparer = new ProjectionComparer((string input) => input.Split('|')[1]);
var results = resultsArray.Distinct(comparer);

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Try something like:

resultArray.Select(p => p.Split('|')).Select(p => new { Name = p[0], Address = p[1] }).GroupBy(p => p.Address).Select(p => p.First()).ToArray();