Join a string using delimiters

Question

What is the best way to join a list of strings into a combined delimited string. I\'m mainly concerned about when to stop adding the delimiter. I\'ll use C# for my example

Answer 1

From http://dogsblog.softwarehouse.co.zw/post/2009/02/11/IEnumerable-to-Comma-Separated-List-(and-more).aspx

A pet hate of mine when developing is making a list of comma separated ids, it is SO simple but always has ugly code.... Common solutions are to loop through and put a comma after each item then remove the last character, or to have an if statement to check if you at the begining or end of the list. Below is a solution you can use on any IEnumberable ie a List, Array etc. It is also the most efficient way I can think of doing it as it relies on assignment which is better than editing a string or using an if.

public static class StringExtensions
{
    public static string Splice(IEnumerable args, string delimiter)
    {
        StringBuilder sb = new StringBuilder();
        string d = "";
        foreach (T t in args)
        {
            sb.Append(d);
            sb.Append(t.ToString());
            d = delimiter;
        }
        return sb.ToString();
    }
}

Now it can be used with any IEnumerable eg.

StringExtensions.Splice(billingTransactions.Select(t => t.id), ",")

to give us 31,32,35