z czym to się je?

using System;

namespace Aspire.SKM {

    public class SkmSession {
        static void Main(string[] args)
        {
            if (1 == 1)
            {
    	        Console.WriteLine("Hello World!");	
            }
        }	
    }
}

public class Hello {

  public static void main(String[] args) {
    if (1 == 1) {
        System.out.print("Hello World");
    }
  }
}

using System;

namespace Aspire.SKM {

    public class SkmSession {
        static void Main(string[] args)
        {
            if (1 == 1)
            {
    	        Console.WriteLine("Hello World!");	
            }
        }	
    }
}

public class Hello {

  public static void main(String[] args) {
    if (1 == 1) {
        System.out.print("Hello World");
    }
  }
}

C# (pronounced see sharp, like the musical note C♯, but written with the number sign)[b] is a general-purpose, multi-paradigm programming language encompassing strong typing, lexically scoped, imperative, declarative, functional, generic, object-oriented (class-based), and component-oriented programming disciplines.

(...) object-oriented (class-based), and component-oriented (...)

virtual

interaface

package com.journaldev.java.legacy;

public class MyApplication {

	private EmailService emailService;
	
	public MyApplication(EmailService emailService) {
		this.emailService = emailService;
	}
	
	public void processMessages(String msg, String rec){
		this.email.sendEmail(msg, rec);
	}
}

Why no interface?

EmailService

IEmailService

In Java all instance methods are virtual by default

In C# it's the opposite

Composition vs Inheritance

JVM and .NET

Both Virtual Machines (VMs)
Both include garbage collection
Both employ stack-based operations
Both include runtime-level security
Both have methods for exception handling

How about functional programming?

C# has some functional-like features...

local functions
pattern matching
method chains, pipelines
extension methods
delegates and high-order functions
expressions
tuples
nullable references

.. ande more are coming

discriminated unions
records
parameter null-checking
attributes on local functions [NotNull]
...

+ MVC

Manager paczek (zamiast Mavena czy CocoaPods)

You don't need Windows to start with .NET

CORE

API + MVC

// PUT: api/TodoItems/5
[HttpPut("{id}")]
public async Task<IActionResult> PutTodoItem(long id, TodoItem todoItem)
{
    if (id != todoItem.Id)
    {
        return BadRequest();
    }

    _context.Entry(todoItem).State = EntityState.Modified;

    try
    {
        await _context.SaveChangesAsync();
    }
    catch (DbUpdateConcurrencyException)
    {
        if (!TodoItemExists(id))
        {
            return NotFound();
        }
        else
        {
            throw;
        }
    }

    return NoContent();
}

You can still write some frontend in .NET ;)

@page "/counter"

<h1>Counter</h1>

<p>Current count: @currentCount</p>

<button class="btn btn-primary" @onclick="IncrementCount">Click me</button>

@code {
    private int currentCount = 0;

    [Parameter]
    public int IncrementAmount { get; set; } = 1;

    private void IncrementCount()
    {
        currentCount += IncrementAmount;
    }
}