Introduction to .NET with C#

1. Introduction

In this section we will learn about what is .NET, how to setup the development environment and how to start making some console apps. Apart from that we will also learn how to take input from the user in the console for making interactive applications.

What is the .NET Platform exactly?

Creating a Console Application

Taking input from the User

Task - Building a Simple Calculator

Dealing with Exceptions caused by User Input

Task - Improving the Calculator

Reading Files

Writing Files

Task - File Based Calculator

2. Asynchronous Programming and Introduction to Web Services

In this section, we will be learning how to perform multiple tasks at once to improve the performance and responsiveness of applications. We will also briefly learn what Web Services and APIs are. This will give us an introduction to how the internet and websites work. We will also learn how to use APIs.

What is Asynchronous Programming?

Implementing an Asynchronous Method

Task - Asynchronously Reading Files

Introduction to APIs

Making a GET Request

Task - Using an API

Handling Exceptions caused by HTTP Request

Task - Exception Handling for API Response

3. Introduction to Databases with .NET

In this section we will learn what are databases, specifically what are SQL databases and how to create them. We will study their structure and will learn to perform some basic operations on the databases. This chapter will serve as an introduction to ADO.NET which is a .NET module used for interacting with databases.

What is a Database?

Structure of a Relational Database

Setting Up A MySQL Server

Connecting to the MySQL Server

Task - Writing Connection Strings

Executing Commands

Task - Executing MySQL Commands

MySqlCommand Methods

Task - Connecting to a MySQL Database and Executing Commands

4. CRUD Operations with MySQL

In this section, we'll cover the fundamental CRUD operations (Create, Read, Update, Delete) using SQL. We'll explore SQL syntax at a basic level and recap how to implement each SQL statement in C# code. While some parts may serve as a review from the previous section, this will provide a solid understanding of essential database concepts, enabling you to understand both the SQL and C# code and write it independently.

Introduction to CRUD Operations

Installing & Using MySQL Workbench

5. Optimizing Database Operations

In this chapter we will learn about additional functions or methods for making database management more efficient. For-example executing multiple SQL commands at once using Stored Procedures, and retrieving data in bulk from the SQL database using DataSet.

Stored Procedures

Task - Executing Stored Procedures

DataReader vs DataSet

DataAdapter & DataSet

Task - Reading Tables using MySqlDataAdapter

What's Next?

Task - Using an API

There is a free public API, it is called Numbers API. It has multiple endpoints, one of which returns a random fact about any date of the year.

The base code is given. The program takes a month number and a day number from the user.

Task: Make a request to the Numbers API to retrieve a random fact about that date.

Guidelines:

The url at which you make a request will depend upon the date which the user enters. It means that the URL will not be fixed, rather, it would follow a format. You can read about the format of this API at: the Numbers API website.

The format of retrieving a fact about some date is: http://numbersapi.com/<month>/<day>/date where <month> represents the number of the month and <day> represents the number of the day. For example, if the user enters 11 for the month (which represents the 11th month - November) and 6 for the day, the URL will be: http://numbersapi.com/11/6/date

Steps:

Create a new variable called url and store the URL following the format explained in the Guidelines. You might need to use string formatting;
Create a new HttpClient() object;
Use the HttpClient object and make a GET request to the url;
Store the response of the HTTP request into a HttpResponseMessage object;
Extract the raw message text from the HttpResponseMessage object using ReadAsStringAsync method;
Display the message.

Note
This task does not have unit tests. You can verify the correctness of your code based on a successful response from the API.

Link to the Task: GitHub

1. You can make an HTTP request using an HttpClient object.
2. The response of the HTTP request can be stored in an HttpResponseMessage object.


public class NumbersFact
{
    public static async Task Main()
    {
        Console.WriteLine(">> This program gives you a random fact about any day of the year. ");

        Console.Write("Enter the number of month (1-12): ");
        int month = int.Parse(Console.ReadLine());

        Console.Write("Enter the number of day: ");
        int day = int.Parse(Console.ReadLine());

        // Write code below this line
        string url = $"http://numbersapi.com/{month}/{day}/date";
        HttpClient client = new HttpClient();
        HttpResponseMessage response = await client.GetAsync(url);
        string responseContent = await response.Content.ReadAsStringAsync();
        Console.WriteLine("Fact: " + responseContent);
        // Write code above this line
    }
}

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Зміст курсу

Introduction to .NET with C#

1. Introduction

What is the .NET Platform exactly?Creating a Console Application Taking input from the User Task - Building a Simple Calculator Dealing with Exceptions caused by User Input Task - Improving the Calculator Reading Files Writing Files Task - File Based Calculator

2. Asynchronous Programming and Introduction to Web Services

What is Asynchronous Programming?Implementing an Asynchronous Method Task - Asynchronously Reading Files Introduction to APIs Making a GET Request Task - Using an API Handling Exceptions caused by HTTP Request Task - Exception Handling for API Response

3. Introduction to Databases with .NET

What is a Database?Structure of a Relational Database Setting Up A MySQL Server Connecting to the MySQL Server Task - Writing Connection Strings Executing Commands Task - Executing MySQL Commands MySqlCommand Methods Task - Connecting to a MySQL Database and Executing Commands

4. CRUD Operations with MySQL

Introduction to CRUD Operations Installing & Using MySQL Workbench CREATE - Part I Task - Using CREATE CREATE - Part II Task - Using INSERT Read Task - Using SELECT Update Task - Using UPDATE Delete - Part I Delete - Part II Task - Using DELETE

5. Optimizing Database Operations

Stored Procedures Task - Executing Stored Procedures DataReader vs DataSet DataAdapter & DataSet Task - Reading Tables using MySqlDataAdapter What's Next?

Introduction to .NET with C#

Task - Using an API

There is a free public API, it is called Numbers API. It has multiple endpoints, one of which returns a random fact about any date of the year.

The base code is given. The program takes a month number and a day number from the user.

Task: Make a request to the Numbers API to retrieve a random fact about that date.

Guidelines:

Steps:

Create a new variable called url and store the URL following the format explained in the Guidelines. You might need to use string formatting;
Create a new HttpClient() object;
Use the HttpClient object and make a GET request to the url;
Store the response of the HTTP request into a HttpResponseMessage object;
Extract the raw message text from the HttpResponseMessage object using ReadAsStringAsync method;
Display the message.

Note
This task does not have unit tests. You can verify the correctness of your code based on a successful response from the API.

Link to the Task: GitHub

1. You can make an HTTP request using an HttpClient object.
2. The response of the HTTP request can be stored in an HttpResponseMessage object.


public class NumbersFact
{
    public static async Task Main()
    {
        Console.WriteLine(">> This program gives you a random fact about any day of the year. ");

        Console.Write("Enter the number of month (1-12): ");
        int month = int.Parse(Console.ReadLine());

        Console.Write("Enter the number of day: ");
        int day = int.Parse(Console.ReadLine());

        // Write code below this line
        string url = $"http://numbersapi.com/{month}/{day}/date";
        HttpClient client = new HttpClient();
        HttpResponseMessage response = await client.GetAsync(url);
        string responseContent = await response.Content.ReadAsStringAsync();
        Console.WriteLine("Fact: " + responseContent);
        // Write code above this line
    }
}

Все було зрозуміло?

Секція 2. Розділ 6