Convert an Array List to a comma delimited string

Sometimes we need to Convert an  ArrayList to a comma delimited string.

For  example:

If we have a ArrayList of string value then we usually write the following code

   ArrayList alist=new ArrayList();

   alist.Add("One");

   alist.Add("Two");

   alist.Add("Three");

   string strComma = string.Join(",", (string[])alist.ToArray(Type.GetType("System.String")));       

      Console.WriteLine(strComma);

Output :

One, Two, Three

On other hand for type int of ArrayList  we need to write code like:

   ArrayList alist=new ArrayList();

   alist.Add(1);

   alist.Add(2);

   alist.Add(3);

   string strComma = string.Join(",", (int[])alist.ToArray(Type.GetType("System.Int32")));

       Console.WriteLine(strComma);

Output:

1,2,3

The difference between the types of list is needed to write different code. It actually makes it impossible to write a single function for ALL types of list this way.

But we can handle this if we write a generic method like:

public static string ArrayToString(IList array, string delimeter)

        {

            string outputString = "";

            for (int i = 0; i < array.Count; i++)

            {

                if (array[i] is IList)

                {

                   outputString += ArrayToString((IList)array[i], delimeter);

                }

                else

                {

                    outputString += array[i];

                }

                if (i != array.Count - 1)

                    outputString += delimeter;

            }

            return outputString;

        }

We now just call the function by sending the  ArrayList as a array and delimiter string. It doesn’t need to care about the Type of ArrayList

Example:

   ArrayList alist=new ArrayList();

   alist.Add(1);

   alist.Add(2);

   alist.Add(3);

  string strComma =ArrayToString(alist.ToArray(),",");

  Console.WriteLine(strComma);

Output:

1,2,3