What is the LINQ way to implode/join a string array?

Question

I have the following string array:

var sa = new string[] {"yabba","dabba","doo"};

I can convert it to "yabba, dabba, doo" it using string.Join() but what is the super-cool LINQ way of doing it? The Join extension method seems promising but for a novice like me very confusing.

Answer 1

Have you looked at the Aggregate extension method?

var sa = (new[] { "yabba", "dabba", "doo" }).Aggregate((a,b) => a + "," + b);

Answer 2

Why use Linq?

string[] s = {"foo", "bar", "baz"};
Console.WriteLine(String.Join(", ", s));

That works perfectly and accepts any IEnumerable<string> as far as I remember. No need Aggregate anything here which is a lot slower.

Answer 3

I always use the extension method:

public static string JoinAsString<T>(this IEnumerable<T> input, string seperator)
{
    var ar = input.Select(i => i.ToString()).ToArray();
    return string.Join(seperator, ar);
}

Answer 4

I blogged about this a while ago, what I did seams to be exactly what you're looking for:

http://ondevelopment.blogspot.com/2009/02/string-concatenation-made-easy.html

In the blog post describe how to implement extension methods that works on IEnumerable and are named Concatenate, this will let you write things like:

var sequence = new string[] { "foo", "bar" };
string result = sequence.Concatenate();

Or more elaborate things like:

var methodNames = typeof(IFoo).GetMethods().Select(x => x.Name);
string result = methodNames.Concatenate(", ");