第一部分: http://www.cnblogs.com/cgzl/p/8478993.html
第二部分: http://www.cnblogs.com/cgzl/p/8481825.html
由于本文主要是讲 VSCode 开发等, 所以相关等一些 angular/.net core 的知识就相对少讲点.
我把需求改一下, 如图:
由于 efcore 目前还是使用中间表来建立多对多的关系, 所以分类标签这个需求就没什么特别的了, 就去掉吧. 还有电视剧分季这个技术上也是重复的, 也删掉.
目前只剩下电视台和电视剧的维护, 还剩下的知识点是:
集合的 CRUD 操作
对项目结构进行整理, 使用 Unit Of Work 以及 Repository 模式
上传文件
由于 CRUD 画面做起来比较简单, 我相信大家使用该技术的都会, 所以我直接把我写完的代码传上来. 此时页面的操作效果请看视频:
这时的代码:
https://pan.baidu.com/s/1egCmuNT0OxJNwkz0OQ72kA
这里面又一个比较常见的问题, 就是
针对集合的增删改:
上述业务的电视剧的增删改就会出现这种情况:
数据库里面原来有 4 条数据, 而前台操作完, 删除了第 3 条数据, 并且增加了一条数据, 其余数据的内容可能有变化.
这种集合类增删改的思路应该是这样的:
1. 从传进来的集合找出所有新添加的数据 (新添加的数据 Id 通常并不存在, 这是条件), 放在一个临时的集合, 然后添加到 context.
2. 从数据库集合找出所有需要删除的数据 (有一些 id 在传进来的集合找不到的就是), 放在一个集合, 然后从 conetxt 一次性移除.
3. 两个集合都有的数据就是只需要修改内容的数据, 更新即可.
下面开始实现这个功能:
首先确保 Put 方法里, 把电视台下所有的电视剧都读取出来:
接下来, 找到 MappingProfile.cs, 使用 AutoMapper 来实现这个功能.
首先要忽略默认的集合映射:
然后调用 AfterMap 方法做后期手动处理, 代码的意思大概是这样:
或者, 也可以用 Linq 做一些重构:
回到画面试一下编辑功能:
然后添加和删除:
查看结果:
OK.
项目重构
下面, 我们使用 Unit Of Work 以及 Repository Pattern 对项目进行重构:
由于这部分也很简单, 并且也不是这篇文章的重点, 我就直接贴出重构后的代码吧:
- Database/TvRepostiory.cs:
- using System.Collections.Generic;
- using System.Threading.Tasks;
- using Microsoft.EntityFrameworkCore;
- using Tv.Models;
- namespace Tv.Database
- {
- public class TvRepository : ITvRepostitory
- {
- private readonly TvContext context;
- public TvRepository(TvContext context)
- {
- this.context = context;
- }
- public async Task<List<TvNetwork>> GetTvNetworksAsync()
- {
- return await context.TvNetworks.Include(x => x.TvShows).ToListAsync();
- }
- public async Task<TvNetwork> GetTvNetworkByIdAsync(int id, bool includeRelated = true)
- {
- if (includeRelated)
- {
- return await context.TvNetworks.Include(x => x.TvShows).SingleOrDefaultAsync(x => x.Id == id);
- }
- return await context.TvNetworks.FindAsync(id);
- }
- public void AddTvNetwork(TvNetwork model)
- {
- context.TvNetworks.Add(model);
- }
- public void RemoveTvNetwork(TvNetwork model)
- {
- context.TvNetworks.Remove(model);
- }
- }
- }
- Database/ITvRepository.cs:
- using System.Collections.Generic;
- using System.Threading.Tasks;
- using Tv.Models;
- namespace Tv.Database
- {
- public interface ITvRepostitory
- {
- Task<List<TvNetwork>> GetTvNetworksAsync();
- Task<TvNetwork> GetTvNetworkByIdAsync(int id, bool includeRelated = true);
- void AddTvNetwork(TvNetwork model);
- void RemoveTvNetwork(TvNetwork model);
- }
- }
- Database/UnitOfWork.cs:
- using System.Threading.Tasks;
- namespace Tv.Database
- {
- public class UnitOfWork : IUnitOfWork
- {
- private readonly TvContext context;
- public UnitOfWork(TvContext context)
- {
- this.context = context;
- }
- public async Task SaveAsync()
- {
- await context.SaveChangesAsync();
- }
- }
- }
- Database/IUnitOfWork.cs:
- using System.Threading.Tasks;
- namespace Tv.Database
- {
- public interface IUnitOfWork
- {
- Task SaveAsync();
- }
- }
- Startup.cs:
- public void ConfigureServices(IServiceCollection services)
- {
- services.AddAutoMapper();
- // services.AddDbContext<TvContext>(opt => opt.UseSqlServer(Configuration["ConnectionStrings:Default"]));
- services.AddDbContext<TvContext>(opt => opt.UseSqlServer(Configuration.GetConnectionString("Default")));
- services.AddScoped<ITvRepostitory, TvRepository>();
- services.AddScoped<IUnitOfWork, UnitOfWork>();
- services.AddMvc();
- }
- TvController.cs:
- using System.Collections.Generic;
- using System.Threading.Tasks;
- using AutoMapper;
- using Microsoft.AspNetCore.Mvc;
- using Microsoft.EntityFrameworkCore;
- using Tv.Database;
- using Tv.Models;
- using Tv.ViewModels;
- namespace Tv.Controllers
- {
- public class TvController : Controller
- {
- private readonly ITvRepostitory repostiory;
- private readonly IUnitOfWork unitOfWork;
- private readonly IMapper mapper;
- public TvController(ITvRepostitory repostiory, IUnitOfWork unitOfWork, IMapper mapper)
- {
- this.repostiory = repostiory;
- this.unitOfWork = unitOfWork;
- this.mapper = mapper;
- }
- [HttpGet("api/tvnetworks")]
- public async Task<IEnumerable<TvNetworkViewModel>> GetTvNetworks()
- {
- var models = await repostiory.GetTvNetworksAsync();
- var vms = mapper.Map<List<TvNetwork>, List<TvNetworkViewModel>>(models);
- return vms;
- }
- [HttpGet("api/tvnetworks/{id}")]
- public async Task<IActionResult> Get(int id)
- {
- var model = await repostiory.GetTvNetworkByIdAsync(id);
- var vm = mapper.Map<TvNetwork, TvNetworkViewModel>(model);
- return Ok(vm);
- }
- [HttpPost("api/tvnetworks")]
- public async Task<IActionResult> Post([FromBody]TvNetworkUpdateViewModel vm)
- {
- if (!ModelState.IsValid)
- {
- return BadRequest(ModelState);
- }
- var model = mapper.Map<TvNetworkUpdateViewModel, TvNetwork>(vm);
- repostiory.AddTvNetwork(model);
- await unitOfWork.SaveAsync();
- var result = mapper.Map<TvNetwork, TvNetworkViewModel>(model);
- return Ok(result);
- }
- [HttpPut("api/tvnetworks/{id}")]
- public async Task<IActionResult> Put(int id, [FromBody]TvNetworkUpdateViewModel vm)
- {
- if (!ModelState.IsValid)
- {
- return BadRequest(ModelState);
- }
- var dbModel = await repostiory.GetTvNetworkByIdAsync(id);
- if (dbModel == null)
- {
- return NotFound();
- }
- var model = mapper.Map<TvNetworkUpdateViewModel, TvNetwork>(vm, dbModel);
- await unitOfWork.SaveAsync();
- var result = mapper.Map<TvNetwork, TvNetworkViewModel>(model);
- return Ok(result);
- }
- [HttpDelete("api/tvnetworks/{id}")]
- public async Task<IActionResult> Delete(int id)
- {
- var model = await repostiory.GetTvNetworkByIdAsync(id, includeRelated: false);
- if (model == null)
- {
- return NotFound();
- }
- repostiory.RemoveTvNetwork(model);
- await unitOfWork.SaveAsync();
- return NoContent();
- }
- }
- }
再操作下画面, 没有任何问题.
今天先写到这, VSCode 的开发速度还是非常快的.
还剩下最后一部分 -- 上传文件.
来源: https://www.cnblogs.com/cgzl/p/8525541.html