用VSCode开发一个基于asp.net core 2.0/sql server linux(docker)/ng5/bs4的项目(3)

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.