ASP.NET Core WebApi + EF Core (CRUD implemented using Swagger test API)

EF has two different versions, namely Entity Framework Core and Entity Framework 6

EF Core: lightweight, extensible, cross-platform, reference EF6, a new platform, a small learning curve, introduce some new features ( bulk deletion )

EF 6: heavy, stable, and Microsoft has no intention to carry out a large version of the upgrade can not be cross-platform.

How to achieve EFCore function

1. Create ASP.NET Core Web Application

2, the new class TodoItem

　　First, create a new folder> Models

　　Add TodoItem in class Models

1 public class TodoItem
2     {
3         public long Id { get; set; }
4         public string Name { get; set; }
5         public bool IsComplete { get; set; }
6     }

3. Add the database context

　　Select Management NuGet package

　　Select "Browse" tab, and then enter in the search box Microsoft.EntityFrameworkCore.SqlServer .

　　Select "Microsoft.EntityFrameworkCore.SqlServer" in the left pane.

　　Select the right pane of the "project" check box, and then select "Install."

　　Using the above described added again Microsoft.EntityFrameworkCore.InMemory NuGet package

　　After two NuGet installation is complete, then a new class Models in TodoContext

public class TodoContext : DbContext
    {
        public TodoContext(DbContextOptions<TodoContext> options)
            : base(options)
        {
        }

        public DbSet<TodoItem> TodoItems { get; set; }
    }

4, registration database context

　　Sqlserver to create a database connection statement in the startup configuration file appsettings.json

  "ConnectionStrings": {
    "todoContext": "server=.;database=TodoDatas;uid=sa;pwd=123456"
  }

　　Go to the Startup class that implements the constructor Startup class registration database context ConfigureServices

public  class the Startup 
    { 
        public the Startup (IConfiguration Configuration) 
        { 
            the Configuration = Configuration; 
        } 
        public IConfiguration the Configuration { GET ;}
         // This method is called at run time.
        // You can use this method to add service to a container such as ASP.NET Core MVC, Entity Framework Core and the Identity 
         // For more information about configuring the application, you can view https://go.microsoft.com/fwlink/? = 398.94 thousand the LinkID 
        public  void ConfigureServices (IServiceCollection Services) 
        { 
            // use sqlserver database
            services.AddDbContext <TodoContext> (opt => 
               opt.UseSqlServer (Configuration.GetConnectionString ( " todoContext " ))); 
            services.AddControllers (); 
            services.AddMvcCore (); 
        } 

        // This method is invoked at run time
         // can using this method to configure the HTTP request pipeline / pipeline for defining middleware request 
        public  void the configure (App IApplicationBuilder, IWebHostEnvironment the env) 
        { 
            IF (env.IsDevelopment ()) 
            { 
                app.UseDeveloperExceptionPage (); 
            } 

            app.UseRouting () ; 

            app.UseEndpoints (Endpoints =>
            {
                endpoints.MapControllers();
            });
        }
    }

5, the installation migration package - generating a database (SQLServer) through code

　　Open the Package Manager Console

　　Input: Add-Migration InitDatabase

　　Input: update-database to generate the database

6, adding a controller

　　New Folder> Controllers

　　Add TodoController controller Controllers in

namespace EFCoreTest.Controllers 
{ 
    // If the access path 404 needs to be configured for the route 
    [the Route ( " API / [Controller] " )] 
    [ApiController] 
    public  class TodoController: the Controller 
    { 
        Private  Readonly TodoContext _context;
         public TodoController (TodoContext context) 
        { 
            _context = context; IF (_context.TodoItems.Count () == 0 ) 
            { 
                // if the set is empty, then create a new TodoItem,
                 // which means you can't delete all TodoItems. _context.TodoItems.Add(new TodoItem { Name = "Item1" }); _context.SaveChanges(); 
                _context.TodoItems.Add(new TodoItem { Id = 1, Name = "Item1", IsComplete = false });
                _context.TodoItems.Add(new TodoItem { Id = 2, Name = "Item2", IsComplete = false });
                _context.TodoItems.Add(new TodoItem { Id = 3, Name = "Item3", IsComplete = true });
                _context.SaveChanges();
            }
        }

        [HttpGet]
        public IEnumerable<TodoItem> GetAll() 
        {
            return _context.TodoItems.ToList();
        }
    } 
}

　　4.4 to access the page you need to set route

　　Go launchSettings.json, adding "launchUrl": "api / Todo"

{
  "iisSettings": {
    "windowsAuthentication": false, 
    "anonymousAuthentication": true, 
    "iisExpress": {
      "applicationUrl": "http://localhost:54029",
      "sslPort": 44320
    }
  },
  "profiles": {
    "IIS Express": {
      "commandName": "IISExpress",
      "launchBrowser": true,
      "launchUrl": "api/Todo",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    },
    "EFCoreTest": {
      "commandName": "Project",
      "launchBrowser": true,
      "applicationUrl": "https://localhost:5001;http://localhost:5000",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    }
  }
}

7, CRUD

namespace EFCoreTest.Controllers 
{ 
    // If the access path 404 needs to be configured for the route 
    [the Route ( " API / [Controller] " )] 
    [ApiController] 
    public  class TodoController: the Controller 
    { 
        Private  Readonly TodoContext _context;
         public TodoController (TodoContext context) 
        { 
            _context = context;
             IF (_context.TodoItems.Count () == 0 ) 
            { 
                // if the set is empty, then create a new TodoItem,
                 // which means you can't delete all TodoItems. _context.TodoItems.Add(new TodoItem { Name = "Item1" }); _context.SaveChanges(); 
                _context.TodoItems.Add(new TodoItem { Name = "Item1", IsComplete = false });
                _context.TodoItems.Add(new TodoItem { Name = "Item2", IsComplete = false });
                _context.TodoItems.Add(new TodoItem { Name = "Item3", IsComplete = true });

                _context.SaveChanges();
            }
        }

        [HttpGet]
        public IEnumerable<TodoItem> GetAll()
        {
            return _context.TodoItems.ToList();
        }

        /// <summary>
        /// 根据Id查找数据
        /// </summary>
        /// <param name="Id">序号</param>
        /// <returns></returns>
        [HttpGet("{Id}", Name = "GetTodo")]
        public async Task<TodoItem> GetByID(int Id)
        {
            var item = await _context.TodoItems.FirstOrDefaultAsync(t => t.Id == Id);

            return item;
        }

        /// <summary>
        /// 创建
        /// </summary>
        /// <param name="item"></param>
        /// <returns></returns>
        [HttpPost]
        public async Task<IActionResult> Create([FromBody] TodoItem item)
        {
            if (item == null)
            {
                return BadRequest();
            }
            else
            {
                _context.TodoItems.Add(item);
                await _context.SaveChangesAsync();
                return Ok(item);
            }
        }

        /// <summary>
        /// 修改
        /// </summary>
        /// <param name="Id"></param>
        /// <param name="item"></param>
        /// <returns></returns>
        [HttpPut("{id}")]
        public async Task<IActionResult> Update(int id, [FromBody] TodoItem item)
        {
            if (item == null)
            {
                return BadRequest();
            }
            else
            {
                var todo = _context.TodoItems.SingleOrDefault(t => t.Id == id);

                if (todo == null)
                {
                    return NotFound();
                }
                else
                {
                    todo.IsComplete = item.IsComplete;
                    todo.Name = item.Name;

                    _context.TodoItems.Update(todo);
                    await _context.SaveChangesAsync();

                    return Ok(todo);
                }

            }
        }

        /// <summary>
        /// 删除
        /// </summary>
        /// <param name="Id"></param>
        /// <returns></returns>
        [HttpDelete("{Id}")]
        public async Task<IActionResult> Delete(int Id)
        {
            var todo = _context.TodoItems.SingleOrDefault(t => t.Id == Id);

            if (todo == null)
            {

                return NotFound();
            }
            else
            {
                _context.TodoItems.Remove(todo);
                await _context.SaveChangesAsync();

                return Ok();
            }
        }
    }
}

　　Operating results show

8, using a swagger

　　Swagger both the API documentation management and test functions

　　Open the Package Manager Console

　　输入：Install-Package Swashbuckle.AspNetCore

　　After successful installation to Startup type, to swagger middle added to the request pipeline, the need to add swaggergen method ConfigureServices method startup class,

　　To enable this middleware, we also need to call useswagger method Configure method startup class.

public  class the Startup 
    { 
        public the Startup (IConfiguration Configuration) 
        { 
            the Configuration = Configuration; 
        } 
        public IConfiguration the Configuration { GET ;}
         // This method is called at run time.
        // You can use this method to add service to a container such as ASP.NET Core MVC, Entity Framework Core and the Identity 
         // For more information about configuring the application, you can view https://go.microsoft.com/fwlink/? = 398.94 thousand the LinkID 
        public  void ConfigureServices (IServiceCollection Services) 
        { 
            // use sqlserver database
            services.AddDbContext<TodoContext>(opt =>
               opt.UseSqlServer(Configuration.GetConnectionString("todoContext")));
            services.AddControllers();
            services.AddMvcCore();

            services.AddSwaggerGen(c =>
            {
                c.SwaggerDoc("v1", new OpenApiInfo { Title = "My API", Version = "v1" });
            });

        method may be used to configure the HTTP request pipeline / pipeline for definition request middleware//This method is called at run time
        //
        }
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseSwagger();

            app.UseSwaggerUI(c =>
            {
                c.SwaggerEndpoint("/swagger/v1/swagger.json", "My API V1");
            });

            app.UseRouting();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
            });
        }
    }

　　Enter the path: HTTPS: // localhost: 44320 / Swagger / index.html

　　Show results

　　Source Download: https: //pan.baidu.com/s/1oJbjC4ph8zJIkAujUExDzQ extraction code: meyl

　　Attached PDF Development Guide

　　Follow-up will continue to update other information, like please pay attention to Oh! .

ASP.NET Core WebApi + EF Core (CRUD implemented using Swagger test API)

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