Book Image

The Modern C# Challenge

By : Rod Stephens
Book Image

The Modern C# Challenge

By: Rod Stephens

Overview of this book

C# is a multi-paradigm programming language. The Modern C# Challenge covers with aspects of the .NET Framework such as the Task Parallel Library (TPL) and CryptoAPI. It also encourages you to explore important programming trade-offs such as time versus space or simplicity. There may be many ways to solve a problem and there is often no single right way, but some solutions are definitely better than others. This book has combined these solutions to help you solve real-world problems with C#. In addition to describing programming trade-offs, The Modern C# Challenge will help you build a useful toolkit of techniques such as value caching, statistical analysis, and geometric algorithms. By the end of this book, you will have walked through challenges in C# and explored the .NET Framework in order to develop program logic for real-world applications.
Table of Contents (17 chapters)
Title Page
Copyright and Credits
Packt Upsell
Free Chapter
Dates and Times
Files and Directories
Advanced C# and .NET Features


The following sections describe solutions to the preceding problems. You can download the example solutions to see additional details and to experiment with the programs at

91. Caesar cipher

This problem is relatively straightforward. Simply loop through the message's letters and shift them by some amount.



The example solution uses the following string extension method to encrypt a string:

// Use a Caesar cipher to encrypt the plaintext.
public static string CaesarEncrypt(this string plaintext, int shift)
    plaintext = plaintext.StripText();

    // Encrypt.
    char[] chars = new char[plaintext.Length];
    for (int i = 0; i < plaintext.Length; i++)
        int ch = plaintext[i] - 'A';
        ch = (ch + shift + 26) % 26;
        chars[i] = (char)('A' + ch);
    return new string(chars).ToFiveGrams();

This method calls the StripText extension method described shortly to remove...