Check out example codes for "c# array.join". It will help you in understanding the concepts better.

Code Example 1

var combined = String.Join(",", new String[]{"a","b"});
// a,b

Code Example 2

String Array...
AB
BC
CD
DE
EF
FG
GH
IJ
Result (after joining) = AB*BC*CD*DE*EF*FG*GH*IJ

Code Example 3

using System;
public class Demo {
   public static void Main(string[] args) {
      string[] strArr = {"AB", "BC", "CD", "DE", "EF", "FG", "GH", "IJ" };
      Console.WriteLine("String Array...");
      foreach(string s in strArr) {
         Console.WriteLine(s);
      }
      string str = string.Join("*", strArr);
      Console.WriteLine("Result (after joining) = " + str);
   }
}

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