string.Split C# keeps text outside delimiters

Question

I am trying to take a list of eMail addresses along with first and last names and convert them to a CSV format. My eMail addresses are in the following format:

First, Last <[email protected]>; First, Last <[email protected]>;

The output I need is the following:

[email protected],[email protected]

I am using the following code:

string[] addresses = addresses_Delimited.Split(new Char[] { '<', '>' });

addresses_Delimited is my list of addresses in the original format.

The problem is that it is not eliminating first and last names; instead it is returning first and last names as entries in the array addresses. So, addresses[0] = "First, Last", addresses[1] = "[email protected]", and addresses[2] = "; First, Last". All first and last name entries after the first one have a semicolon in them.

How do I make string.Split remove all text outside "<" and ">"? Do I need to use something else?

Answer 1

Rather than using a Split which does not care that the delimiters are paired up, use a regular expression like this:

<([^>]+)>

When you apply this regex to your input strings, you would capture the content of angular brackets into capturing group number 1:

var s = "First, Last <[email protected]>; First, Last <[email protected]>;";
Regex regex = new Regex(@"<([^>]+)>");
foreach (Match m in regex.Matches(s)) {
    Console.WriteLine(m.Groups[1]);
}

Demo.