学习笔记01:Net Core 常用配置

 常用词汇:

1.GUID: 默认值设置 有序：NEWSEQUENTIALID()  无序：NEWID()

2.获取json数据的方法:  IConfiguration["Key:ChidKey"]

常用代码:
1.1. 根据数据库生成实体类和数据连接,放在实体类所在项目生成,几乎不用改动,更方便.

Scaffold-DbContext "Server=(localdb)mssqllocaldb;Database=Blogging;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Test

1.2. startup数据库连接配置与appsettings.json配置

        public StartupDevelopment(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }



services.AddDbContext<MyContext>(options => options.UseSqlServer(Configuration.GetConnectionString("MyContext")));

{
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Warning"
    }
  },
  "ConnectionStrings": {
    "MyContext": "Server=.;Database=BlogDemo;Trusted_Connection=True;MultipleActiveResultSets=true"

  }

}

1.3. HTTPS  HSTS

 services.AddHttpsRedirection(options =>
            {
                options.RedirectStatusCode = StatusCodes.Status307TemporaryRedirect;
                options.HttpsPort = 5001;
            });

            services.AddHsts(options =>
            {
                options.Preload = true;
                options.IncludeSubDomains = true;
                options.MaxAge = TimeSpan.FromDays(60);
                options.ExcludedHosts.Add("example.com");
                options.ExcludedHosts.Add("www.example.com");
            });

1.4. UseStartup<Startup>(); 使用基于环境的类

 .UseStartup(typeof(StartupDevelopment).GetTypeInfo().Assembly.FullName);

1.5.1  表为空填写默认数据,在program.cs修改如下

            // CreateWebHostBuilder(args).Build().Run(); 将词句注释掉,
            var host= CreateWebHostBuilder(args).Build();
            using (var scope=host.Services.CreateScope())
            {
                var services = scope.ServiceProvider;
                var loggerFactory = services.GetRequiredService<ILoggerFactory>();
                try
                {
                    var myContext = services.GetRequiredService<MyContext>();
                    MyContextSeed.SeedAsync(myContext, loggerFactory).Wait();
                }
                catch (Exception e)
                {
                    var logger = loggerFactory.CreateLogger<Program>();
                    logger.LogError(e,"填写默认数据失败");
                }
            }

                host.Run();

1.5.2  数据表为

namespace BlogDemo.Infrastructure.Database
{
    public class MyContextSeed
    {
        public static async Task SeedAsync(MyContext myContext,
                          ILoggerFactory loggerFactory, int retry = 0)
        {
            int retryForAvailability = retry;
            try
            {
                // TODO: Only run this if using a real database
                // myContext.Database.Migrate();

                if (!myContext.Posts.Any())
                {
                    myContext.Posts.AddRange(
                        new List<Post>{
                            new Post{
                                Title = "Post Title 1",
                                Body = "Post Body 1",
                                Author = "Dave",
                                LastModified = DateTime.Now
                            },
                            new Post{
                                Title = "Post Title 2",
                                Body = "Post Body 2",
                                Author = "Dave",
                                LastModified = DateTime.Now
                            },
                            new Post{
                                Title = "Post Title 3",
                                Body = "Post Body 3",
                                Author = "Dave",
                                LastModified = DateTime.Now
                            }
                        }
                    );
                    await myContext.SaveChangesAsync();
                }
            }
            catch (Exception ex)
            {
                if (retryForAvailability < 10)
                {
                    retryForAvailability++;
                    var logger = loggerFactory.CreateLogger<MyContextSeed>();
                    logger.LogError(ex.Message);
                    await SeedAsync(myContext, loggerFactory, retryForAvailability);
                }
            }
        }
    }
}

1.6.1  Serilog,在program.cs的main方法添加

            Log.Logger = new LoggerConfiguration()
                // .MinimumLevel.Debug()
                .MinimumLevel.Error()
                //  .MinimumLevel.Override("Microsoft", LogEventLevel.Information)
                .MinimumLevel.Override("Microsoft", LogEventLevel.Error)
                .Enrich.FromLogContext()
                .WriteTo.Console()
                .WriteTo.File(Path.Combine("logs", @"log.txt"), rollingInterval: RollingInterval.Day)
                .CreateLogger();

1.7.映射

安装nuget :

AutoMapper

AutoMapper.Extensions.Microsoft.DependencyInjection

创建Extensions/MappingProfile.cs 继承于Profile   (using AutoMapper;)

然后在构造函数里添加映射

    public class MappingProfile:Profile
    {
        public MappingProfile()
        {
            CreateMap<Post, PostResource>()
           .ForMember(dest=>dest.UpdaDateTime,opt=>opt.MapFrom(src=>src.LastModified)); 
            CreateMap<PostResource, Post>();
        }
    }

在控制器里使用

var postResources = _mapper.Map<IEnumerable<Post>, IEnumerable<PostResource>>(posts);

1.8 FluentValidation

1.安装 FluentValidation

2.建立PostResourceValidator.添加继承,添加构造函数

    public class PostResourceValidator:AbstractValidator<PostResource>
    {
        public PostResourceValidator()
        {
            RuleFor(x => x.Author)
                .NotNull()
                .WithName("作者")
                .WithMessage("{PropertyName}是必须填写的")
                .MaximumLength(50)
                .WithMessage("{PropertyName}的最大长度是{MaxLength}");
        }
    }

3.在Startup.cs 注册

services.AddTransient<IValidator<PostResource>, PostResourceValidator>();

2.1 翻页 过滤 排序

2.1.1翻页:  Query String  http://localhost:5000/api/posts?pageIndex=2&pageSize=10&orderBy=Id

1.建立 QueryParameters.cs 数据分页方法类 包含.pageIndex, pageSize, orderBy 等分页参数 

2.建立PostParameters.cs post专用的分页类,继承自QueryParameters.cs 即可.(无特殊条件可以不用写其他内容,继承功能够用即可)

3.1把PostParameters 传给PostController.cs 的[HttpGet] 如下:

public async Task<IActionResult> Get(PostParameters postParameters)

3.2把postParameters传给PostController.cs具体的实现方法

原来:
var postList = await _postRepository.GetAllPostAsync();
改为:
var postList = await _postRepository.GetAllPostAsync(postParameters);

3.3给接口添加参数

同时修改接口
原来:
Task<PaginatedList<Post>> GetAllPostAsync();
改为:
Task<PaginatedList<Post>> GetAllPostAsync(PostParameters postParameters);

3.4在实现类添加参数 PostParameters postParameters,同时原来的列表方法修改下如下

原来为直接列出列表数据.
return await _myContext.Post.ToListAsync();
改为:
1.按Id排序
var query = _myContext.Post.OrderBy(x => x.Id);

2.数据分页
var data = await query.Skip(postParameters.PageIndex * postParameters.PageSize)
.Take(postParameters.PageSize).ToListAsync();

2.1 REST

 

2.2 HTTP GET

2.2 状态码

200系列 成功

400系列 客户端引起的错误

500系列 服务器端引起的错误