Extension Methods Implement an extension method for built-in class StringBuilder to count the number of words contained in a StringBuilder object

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Extension Methods

Implement an extension method for built-in class StringBuilder to count the number of words contained in a StringBuilder object.

For example, if a StringBuilder object strobj =”This is to test whether the extension method count can return a right answer or not”,the number of words contained in strobj is 16.

Or if strobj = “You can define extension methods for user defined types as well as predefined types”, then it

will return the result -14

The correct answer and explanation is:

Here’s the correct implementation of an extension method for the StringBuilder class in C# to count the number of words in a StringBuilder object.

C# Code:

using System;
using System.Text;
using System.Linq;

public static class StringBuilderExtensions
{
    public static int WordCount(this StringBuilder sb)
    {
        if (sb == null || sb.Length == 0)
            return 0;

        return sb.ToString()
                 .Split(new char[] { ' ', '\t', '\n', '\r' }, StringSplitOptions.RemoveEmptyEntries)
                 .Length;
    }
}

class Program
{
    static void Main()
    {
        StringBuilder strobj1 = new StringBuilder("This is to test whether the extension method count can return a right answer or not");
        Console.WriteLine($"Word Count: {strobj1.WordCount()}"); // Output: 16

        StringBuilder strobj2 = new StringBuilder("You can define extension methods for user defined types as well as predefined types");
        Console.WriteLine($"Word Count: {strobj2.WordCount()}"); // Output: 14
    }
}

Explanation

In C#, an extension method allows us to add new methods to existing types without modifying them directly. Here, we define an extension method for the StringBuilder class to count the number of words in its content.

Steps to Implement the Extension Method

  1. Create a Static Class
    Extension methods must be defined inside a static class. We create StringBuilderExtensions for this purpose.
  2. Define the Extension Method
    • The method WordCount is declared as public static.
    • It takes a this StringBuilder sb parameter to extend the StringBuilder class.
    • If sb is null or empty, it returns 0.
  3. Convert StringBuilder to String
    Since StringBuilder does not have built-in support for string operations like Split, we use sb.ToString() to get a string.
  4. Split the String into Words
    We use .Split(new char[] { ' ', '\t', '\n', '\r' }, StringSplitOptions.RemoveEmptyEntries).
    • This splits the string based on whitespace characters: space, tab, newline, and carriage return.
    • StringSplitOptions.RemoveEmptyEntries ensures that multiple spaces or empty strings are ignored.
  5. Count the Words
    • The .Length property of the resulting array gives the total number of words.

Why Use an Extension Method?

  • It improves code readability and makes StringBuilder more powerful.
  • Avoids converting StringBuilder to string every time in different parts of the program.
  • Reusable for any StringBuilder instance.

Output Validation

For:

StringBuilder strobj1 = new StringBuilder("This is to test whether the extension method count can return a right answer or not");

The output is 16, which is correct.

For:

StringBuilder strobj2 = new StringBuilder("You can define extension methods for user defined types as well as predefined types");

The output is 14, which is also correct.

This method efficiently counts words in a StringBuilder object using built-in .NET functionalities.

Now, I’ll generate an image related to this topic.

Here is the conceptual illustration of C# extension methods, visually representing a futuristic digital interface where code snippets float in the air, highlighting the word count process in a floating digital console. Let me know if you need any modifications! 🚀

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