Count Occurrences of a Word in a String (LINQ)

class CountWords

{

    static void Main()

    {

        string text = @"Historically, the world of data and the world of objects" +

          @" have not been well integrated. Programmers work in C# or Visual Basic" +

          @" and also in SQL or XQuery. On the one side are concepts such as classes," +

          @" objects, fields, inheritance, and .NET Framework APIs. On the other side" +

          @" are tables, columns, rows, nodes, and separate languages for dealing with" +

          @" them. Data types often require translation between the two worlds; there are" +

          @" different standard functions. Because the object world has no notion of query, a" +

          @" query can only be represented as a string without compile-time type checking or" +

          @" IntelliSense support in the IDE. Transferring data from SQL tables or XML trees to" +

          @" objects in memory is often tedious and error-prone.";

        string searchTerm = "data";

        //Convert the string into an array of words

        string[] source = text.Split(new char[] { '.', '?', '!', ' ', ';', ':', ',' }, StringSplitOptions.RemoveEmptyEntries);

        // Create and execute the query. It executes immediately

        // because a singleton value is produced.

        // Use ToLowerInvariant to match "data" and "Data"

        var matchQuery = from word in source

                         where word.ToLowerInvariant() == searchTerm.ToLowerInvariant()

                         select word;

        // Count the matches.

        int wordCount = matchQuery.Count();

        Console.WriteLine("{0} occurrences(s) of the search term \"{1}\" were found.", wordCount, searchTerm);

        // Keep console window open in debug mode

        Console.WriteLine("Press any key to exit");

        Console.ReadKey();

    }

}

/* Output:

   3 occurrences(s) of the search term "data" were found.

*/