.NET 6 Entity Framework Core Db First（2） 增删改查

基础代码

• 在Program.cs注入DemoContext
• 新建HomeController，继承ControllerBase
• 添加Controller特性，[ApiController] [Route("[controller]/{action=index}")]
• 通过构造函数获取数据库上下文实例(DemoContext) 

接口地址

为了方便测试，这里全部使用了HttpGet，也不需要传参数

1、查询

• http://localhost:5109/home
• http://localhost:5109/home/get/2

2、添加

• http://localhost:5109/home/add

3、修改

• http://localhost:5109/home/edit

4、删除

• http://localhost:5109/home/delete

具体代码

Program.cs

using EFDBFirstDemo.Model.Context;
using Microsoft.EntityFrameworkCore;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

var connectionString = builder.Configuration.GetConnectionString("demo");
builder.Services.AddDbContext<DemoContext>(options => options.UseSqlServer(connectionString));

//数据库异常筛选器
builder.Services.AddDatabaseDeveloperPageExceptionFilter();

builder.Services.AddControllers();

var app = builder.Build();

// Configure the HTTP request pipeline.

app.UseAuthorization();

app.MapControllers();

app.Run();

HomeController.cs

namespace EFDBFirstDemo.API.Controllers
{
    [ApiController]
    [Route("[controller]/{action=index}")]
    public class HomeController : ControllerBase
    {
        public DemoContext _demoContext;

        public HomeController(DemoContext demoContext)
        {
            _demoContext = demoContext;
        }

        public IActionResult Index()
        {
            var result = _demoContext.Students.ToList();

            return Ok(result);
        }

        [Route("{id?}")]
        public async Task<IActionResult> Get(int id)
        {
            var result = await _demoContext.Students.FindAsync(id);
            //var result = _demoContext.Students.FirstOrDefault(l => l.Id == id);
            return Ok(result);
        }

        //[HttpPost]
        public async Task<IActionResult> Add()
        {
            var student = new Student
            {
                StudentName = "张三",
                EnrollmentData = DateTime.Now
            };
            _demoContext.Add(student);
            var result = await _demoContext.SaveChangesAsync();
            return Ok(result);
        }

        //[HttpPost]
        public async Task<IActionResult> Edit()
        {
            var student = new Student
            {
                Id = 2,
                StudentName = "李四",
                EnrollmentData = DateTime.Now
            };
            _demoContext.Update(student);
            var result = await _demoContext.SaveChangesAsync();
            return Ok(result);
        }

        //[HttpPost]
        public async Task<IActionResult> Delete()
        {
            var student = new Student
            {
                Id = 1
            };
            //_demoContext.Students.Remove(student);
            _demoContext.Remove(student);
            var result = await _demoContext.SaveChangesAsync();
            return Ok(result);
        }
    }
}