using System;

using System.Text.RegularExpressions;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var pattern = @"\[([\d-.]+)[, ]+([\d-.]+)\][, ]+\[([\d-.]+)[, ]+([\d-.]+)\]";

        var s = "1: ([37.788353, -122.387695], [37.829853, -122.294312]) 2: ([37.429615, -122.087631], [37.487391, -122.018967]) 3: ([37.474858, -122.131577], [37.529332, -122.056046]) 4: ([37.532599,-122.218094], [37.615863,-122.097244]) 5: ([37.516262,-122.198181], [37.653383,-122.151489]) 6: ([37.504824,-122.181702], [37.633266,-122.121964])";

        var matches = Regex.Matches(s, pattern).Cast<Match>();

        foreach (var str in matches)

        {

            Console.WriteLine(string.Format("x1: {0}, y1: {1}, x2: {2}, y2: {3}", 

                                            str.Groups[1],str.Groups[2], str.Groups[3], str.Groups[4]));

        }

    }

}