asp.net core 2.1 WebApi 快速入门

参考：https://docs.microsoft.com/zh-cn/aspnet/core/tutorials/first-web-api?view=aspnetcore-2.1

官网的例子#

直接去看，这里写用到的代码

创建一个model

namespace TodoApi.Models
{
    public class TodoItem
    {
        public long Id { get; set; }
        public string Name { get; set; }
        public bool IsComplete { get; set; }
    }
}

创建数据库上下文

using Microsoft.EntityFrameworkCore;

namespace TodoApi.Models
{
    public class TodoContext : DbContext
    {
        public TodoContext(DbContextOptions<TodoContext> options)
            : base(options)
        {
        }

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

Register the database context

 public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<TodoContext>(opt =>
                            opt.UseInMemoryDatabase("TodoList"));
							
            services.AddMvc()
                .SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
        }

添加控制器 TodoController

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Cors;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using TodoApi.Models;

namespace TodoApi.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    [EnableCors("any")]
    public class TodoController : ControllerBase
    {
        private readonly TodoContext _context;

        public TodoController(TodoContext context)
        {
            _context = context;

            if (_context.TodoItems.Count() == 0)
            {
                // Create a new TodoItem if collection is empty,
                // which means you can't delete all TodoItems.
                _context.TodoItems.Add(new TodoItem { Name = "Item1" });
                _context.SaveChanges();
            }
        }


        // GET api/todo
        [HttpGet]
        public ActionResult<List<TodoItem>> GetAll()
        {
            return _context.TodoItems.ToList();
        }


        // GET api/todo/{id}
        [HttpGet("{id}", Name = "GetTodo")]
        public ActionResult<TodoItem> GetById(long id)
        {
            var item = _context.TodoItems.Find(id);
            if (item == null)
            {
                return NotFound();
            }
            return item;
        }


        //POST /api/todo/  
        //Postman: Body->Raw->Json-> {"name":"Item2~","isComplete":false}
        //Header:  Location →http://localhost:64425/api/Todo/2
        [HttpPost]
        public ActionResult Create(TodoItem item)
        {
            _context.TodoItems.Add(item);
            _context.SaveChanges();

            return CreatedAtRoute("GetTodo", new { id = item.Id }, item);
        }



        [HttpPut("{id}")]
        public ActionResult Update(long id, TodoItem item)
        {
            var todo = _context.TodoItems.Find(id);
            if (todo == null)
            {
                return NotFound();
            }

            todo.IsComplete = item.IsComplete;
            todo.Name = item.Name;

            _context.TodoItems.Update(todo);
            _context.SaveChanges();
            return NoContent();
        }

        [HttpDelete("{id}")]
        public IActionResult Delete(long id)
        {
            var todo = _context.TodoItems.Find(id);
            if (todo == null)
            {
                return NotFound();
            }

            _context.TodoItems.Remove(todo);
            _context.SaveChanges();
            return NoContent();
        }
    }
}

然后可以调用了。上面代码已经设置跨域 Microsoft.AspNetCore.Cors;

跨域#

1.全局配置中启用跨域处理，命名为‘any’，任何都可以访问

public void ConfigureServices(IServiceCollection services)
{
    //配置跨域处理
    services.AddCors(options =>
    {
        options.AddPolicy("any", builder =>
        {
            builder.AllowAnyOrigin() //允许任何来源的主机访问
            .AllowAnyMethod()
            .AllowAnyHeader()
            .AllowCredentials();//指定处理cookie
        });
    });
}

2.在控制器或Action的方法注释上使用对应名称的 跨域规则，
[EnableCors("any")]

    [Produces("application/json")]
    [Route("api/Menu")]
    [EnableCors("any")] //设置跨域处理的 代理
    public class MenuController : Controller
    {
    }

cookie#

1.后台通过HttpContext上下文可以直接操作Cookie
2.前台JQuery的ajax请求，需要携带withCredentials才会将cookie的值保存到客户端

跨域：https://www.cnblogs.com/tianma3798/p/6920704.html