• Szerző: Sallai András
• Copyright © Sallai András, 2022
• Licenc: CC Attribution-Share Alike 4.0 International
• Web: https://szit.hu

A Entity Framework Core könnyed hozzáférést biztosít az adatbázisokhoz.

Parancssoros eszköz használatához segítség:

• https://docs.microsoft.com/en-us/ef/core/cli/dotnet

dotnet tool install --global dotnet-ef

dotnet tool install --global dotnet-ef --version 3.0
dotnet tool install --global dotnet-ef --version 5.0
dotnet tool install --global dotnet-ef --version 6.0
dotnet tool install --global dotnet-ef --version 7.0
dotnet tool install --global dotnet-ef --version 8.0

• Linux/macOS $HOME/.dotnet/tools
• Windows %USERPROFILE%\.dotnet\tools

A dotnet-ef útvonalba helyezése:

Bash, zsh, csh vagy tcsh shell esetén:

bash/zsh:

export PATH="$PATH:$HOME/.dotnet/tools/"

csh/tcsh:

set path = ($path $HOME/.dotnet/tools/)

Adjuk a projekthez a függőségeket:

dotnet add package Microsoft.EntityFrameworkCore.Design
dotnet add package Microsoft.EntityFrameworkCore
dotnet add package Pomelo.EntityFrameworkCore.MySql

• A Design kell a migrációs fájlok készítéséhez.

dotnet add package Microsoft.EntityFrameworkCore.Design --version 7.0
dotnet add package Microsoft.EntityFrameworkCore --version 7.0
dotnet add package Pomelo.EntityFrameworkCore.MySql --version 7.0

appsettings.Development.json

{
  "ConnectionStrings": {
    "DefaultConnection": "server=localhost;user=muni;password=titok;database=muni"
  }
}

Program.cs

global using App01.Data;
global using Microsoft.EntityFrameworkCore;
global using Pomelo.EntityFrameworkCore.MySql;
 
var builder = WebApplication.CreateBuilder(args);
 
// Add services to the container.
 
builder.Services.AddControllers();
 
 
builder.Services.AddDbContext<DataContext>(options => 
{
    var connectionString = builder.Configuration.GetConnectionString("DefaultConnection");
    var serverVersion = new MySqlServerVersion(new Version(8, 0, 27));    
    options.UseMySql(connectionString, serverVersion);
});
 
//...

Data/DataContext.cs

using Microsoft.EntityFrameworkCore;
 
namespace App01.Data
{
    public class DataContext : DbContext
    {
 
    }
}

Data/DataContext.cs

using Microsoft.EntityFrameworkCore;
using Pomelo.EntityFrameworkCore.MySql;
 
 
namespace App01.Data
{
    public class DataContext : DbContext
    {
        public DbSet<Employee> Employees { get; set; } = null!;
 
        public DataContext(DbContextOptions<DataContext> options) : base(options) {}
    }
}

Migrációs fájlok készítése:

dotnet ef migrations add InitialCreate

Tábla létrehozása:

dotnet ef database update

Controllers/EmployeeController.cs

using Microsoft.AspNetCore.Mvc;
 
namespace App01.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class EmployeeController : ControllerBase
    {
 
        private readonly DataContext _context;
        public EmployeeController(DataContext context)
        {
            _context = context;
        }
 
        [HttpGet]
        public async Task<ActionResult<List<Employee>>> Get()
        {
            return Ok(await _context.Employees.ToListAsync());
        }
 
        [HttpGet("{id}")]
        public async Task<ActionResult<List<Employee>>> Get(int id)
        {
            var dbEmployee = await _context.Employees.FindAsync(id);
            if (dbEmployee == null) {
                return BadRequest("A dolgozó nem található");
            }
            return Ok(dbEmployee);
        }
 
        [HttpPost]
        public async Task<ActionResult<List<Employee>>> AddEmployee(Employee employee)
        {
            _context.Employees.Add(employee);
            await _context.SaveChangesAsync();
            return Ok(await _context.Employees.ToListAsync());
        }
 
        [HttpPut]
        public async Task<ActionResult<List<Employee>>> UpdateEmployee(Employee request)
        {
            var dbEmployee = await _context.Employees.FindAsync(request.Id);
 
            if (dbEmployee == null) {
                return BadRequest("A dolgozó nem található");
            }            
            dbEmployee.Name = request.Name;
            dbEmployee.City = request.City;
            dbEmployee.Salary = request.Salary;
 
            await _context.SaveChangesAsync();
            _context.Employees.Remove(dbEmployee);
            await _context.SaveChangesAsync();
            return Ok(await _context.Employees.ToListAsync());
        }
 
        [HttpDelete("{id}")]
        public async Task<ActionResult<List<Employee>>> Delete(int id)
        {
            var dbEmployee = await _context.Employees.FindAsync(id);
            if (dbEmployee == null) {
                return BadRequest("A dolgozó nem található");
            }
 
            _context.Employees.Remove(dbEmployee);
            await _context.SaveChangesAsync();
            return Ok(await _context.Employees.ToListAsync());
        }
 
    }
}

• https://github.com/andteki/muni