Program:

The source code to demonstrate Linq Aggregate() method, is given below. The given program is compiled and executed successfully on Microsoft Visual Studio.

//C# Program to demonstrate Linq Aggregate() method.

using System;
using System.Linq;

class LinqDemo
{
    static void Main(string[] args)
    {
        string[] Courses = { "BCA", "MCA", "MBA", "MA", "CA", "BBA" };

        string rstString = "";
        
        rstString=Courses.Aggregate((s1, s2) => s1 + ", " + s2);

        Console.WriteLine(rstString);
    }
}

Output:

BCA, MCA, MBA, MA, CA, BBA
Press any key to continue . . .

Explanation:

In the above program, we created an array of strings that contains courses. And then use the Aggregate() method to combine all courses and separate all courses using comma (,) operator in the final string. Here Aggregate() method will return a combined single string.

To use the Aggregate() method, it is mandatory to import "System.Linq" namespace.