一、.Net Core 依賴注入

1. .net core3.1 之前的版本需要手動配置swagger。當前專案.net core5.0版本自動配置完成

2. 跨域配置

   1.下載依賴包

   2.

        //跨域
        services.AddCors(options =>
        {
          options.AddDefaultPolicy(c =>
          {
            //AllowAnyOrigin 來源  AllowAnyMethod 方法  AllowAnyHeader頭部資訊
            c.AllowAnyOrigin().AllowAnyMethod().AllowAnyHeader();
 

​ }); ​ });

3.使用跨域 在路由之後 授權之前

        //路由
        app.UseRouting();
        //使用跨域！！！！
        app.UseCors();
        //授權
        app.UseAuthorization();

3. 遷移命令：

   1.add-migration inir

   2.update-database

4. 不使用駝峰命名規範

   services.AddControllers().AddJsonOptions(options => options.JsonSerializerOptions.PropertyNamingPolicy = null);

5. NLog配置

   安裝nlog包

   2、在專案根部建立 nlog.config（全部小寫）檔案。

   3、使用例項

   <?xml version="1.0" encoding="utf-8" ?>
   <nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       autoReload="true"
       internalLogLevel="Info"
       internalLogFile="c:\temp\internal-nlog-AspNetCore.txt">
   ​
     <!-- enable asp.net core layout renderers -->
     <extensions>
      <add assembly="NLog.Web.AspNetCore"/>
     </extensions>
   ​
     <!-- the targets to write to -->
     <targets>
      <!-- File Target for all log messages with basic details -->
      <target xsi:type="File" name="allfile" fileName="c:\temp\nlog-AspNetCore-all-${shortdate}.log"
          layout="${longdate}|${event-properties:item=EventId_Id:whenEmpty=0}|${uppercase:${level}}|${logger}|${message} ${exception:format=tostring}" />
   ​
      <!-- File Target for own log messages with extra web details using some ASP.NET core renderers -->
      <target xsi:type="File" name="ownFile-web" fileName="c:\temp\nlog-AspNetCore-own-${shortdate}.log"
          layout="${longdate}|${event-properties:item=EventId_Id:whenEmpty=0}|${uppercase:${level}}|${logger}|${message} ${exception:format=tostring}|url: ${aspnet-request-url}|action: ${aspnet-mvc-action}|${callsite}| body: ${aspnet-request-posted-body}" />
   ​
      <!--Console Target for hosting lifetime messages to improve Docker / Visual Studio startup detection -->
      <target xsi:type="Console" name="lifetimeConsole" layout="${level:truncate=4:lowercase=true}: ${logger}[0]${newline}    ${message}${exception:format=tostring}" />
     </targets>
   ​
     <!-- rules to map from logger name to target -->
     <rules>
      <!--All logs, including from Microsoft-->
      <logger name="*" minlevel="Trace" writeTo="allfile" />
   ​
      <!--Output hosting lifetime messages to console target for faster startup detection -->
      <logger name="Microsoft.Hosting.Lifetime" minlevel="Info" writeTo="lifetimeConsole, ownFile-web" final="true" />
   ​
      <!--Skip non-critical Microsoft logs and so log only own logs (BlackHole) -->
      <logger name="Microsoft.*" maxlevel="Info" final="true" />
      <logger name="System.Net.Http.*" maxlevel="Info" final="true" />
     
      <logger name="*" minlevel="Trace" writeTo="ownFile-web" />
     </rules>
   </nlog>
    
   

   4、更新程式.cs 對比原始碼貼上新程式碼

   using NLog.Web;
   namespace ASP.NET_Core_5_NLog_Example
   {
      public class Program
      {
        public static void Main(string[] args)
        {
          var logger = NLogBuilder.ConfigureNLog("nlog.config").GetCurrentClassLogger();
        
        }
   ​
        public static IHostBuilder CreateHostBuilder(string[] args) =>
          Host.CreateDefaultBuilder(args)
            .ConfigureWebHostDefaults(webBuilder =>
            {
              webBuilder.UseStartup<Startup>();
            })
            //！！！！！！複製以下
            .ConfigureLogging(logging =>
            {
              logging.ClearProviders();
              logging.SetMinimumLevel(LogLevel.Trace);
            })
            .UseNLog();  // NLog: Setup NLog for Dependency injection
      }
   }
   ​

   5、配置應用程式安裝. json

   {
     "Logging": {
      "LogLevel": {
      ///修改Default 為  Trace
       "Default": "Trace",
       "Microsoft": "Warning",
       "Microsoft.Hosting.Lifetime": "Information"
      }
     },
     "AllowedHosts": "*"
   }

   6、 寫日誌 將 ILogger 注入控制器：

   using Microsoft.Extensions.Logging;
   ​
   public class HomeController : Controller
   {
      private readonly ILogger<HomeController> _logger;
   ​
      public HomeController(ILogger<HomeController> logger)
      {
        _logger = logger;
   ​
      }
   ​
      public IActionResult Index()
      {
        _logger.LogInformation("測試");
        return View();
     

二、EF Core

1. .net core使用EF core如下

2. 引用依賴包 using Microsoft.EntityFrameworkCore;

   當前類繼承DBContext 建立上下文

   新增上下文

   連線資料庫