C# Convert List to String with Comma Delimiter | Examples

C# Convert List to String with Comma Delimiter | Examples

A List stores a collection of elements of the same type, which can be either inbuilt or custom-type classes.

The list is a data structure that stores elements in insertion order, and the elements are not sorted.

This tutorial explains how to convert a List of Strings into a string separated by a delimiter, such as a comma.

How to Convert a List of Strings into a Comma-Delimited String

There are multiple ways to convert a List into a comma-separated string.

You can create the list using the IList or IEnumerable interface

    IList<string> numbers = new List<string>{"one","two","three"}; // .NET 4 version
    IEnumerable<string> strEnumerable= new List<string>{"one","two","three"}; // Less than .NET 4 Version
  • Using string.Join Method

The string.Join method takes a separator and an enumerable object, such as a List, and returns a string of separator-delimited strings.


public static string Join<T>(string separator, IEnumerable<T> values)

Here is an example

using System;
using System.Collections.Generic;

public class Program {
  public static void Main() {
    IList<string> numbers = new List<string>{"one","two","three"};
    string str = string.Join(",", numbers);
    Console.WriteLine(str); // one two three

  }
}

The same method works with IEnumerables:

IEnumerable<string> strEnumerable= new List<string>{"one","two","three"};

    string str1 = string.Join(",", strEnumerable);
        Console.WriteLine(str1); // one two three
  }
  • Using StringBuilder AppendJoin Method The AppendJoin() method in StringBuilder takes a separator and a List, returning a comma-separated string.
using System;
using System.Collections.Generic;
using System.Text;

public class Program {
  public static void Main() {
    IList<string> numbers = new List<string>{"one","two","three"};
    string str = string.Join(",", numbers);
   var result= new StringBuilder().AppendJoin(", ", numbers).ToString();

    Console.WriteLine(result); // one two three

  }
}

Both of the above methods work with both IList and IEnumerable.