Entity Framework Core 打印SQL語句

先建個表

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[students](
    [stu_id] [INT] IDENTITY(1,1) NOT NULL,
    [stu_name] [NVARCHAR](20) NULL,
    [stu_gender] [CHAR](1) NULL,
    [stu_phone] [VARCHAR](15) NULL,
    [stu_birthday] [DATE] NULL,
 CONSTRAINT [PK_students] PRIMARY KEY CLUSTERED 
(
    [stu_id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO

然后創建個.NET CORE 3 項目，NuGet安裝

 

 在“程序包管理控制台中”執行

Scaffold-DbContext "Data Source=localhost;Initial Catalog=數據庫名;User ID=用戶名;Password=密碼" Microsoft.EntityFrameworkCore.SqlServer -OutputDir EfModels

這里使用的是DB First模式，如果數據庫還有更新，我們可以增加一個參數（-Force），這樣可以更新

Scaffold-DbContext "Data Source=localhost;Initial Catalog=數據庫名;User ID=用戶名;Password=密碼" Microsoft.EntityFrameworkCore.SqlServer -OutputDir EfModels -Force

在項目中就有了，如圖

 

 添加兩個類

    public class EFLoggerProvider : ILoggerProvider
    {
        public ILogger CreateLogger(string categoryName) => new EFLogger(categoryName);
        public void Dispose() { }
    }

    public class EFLogger : ILogger
    {
        private readonly string categoryName;

        public EFLogger(string categoryName) => this.categoryName = categoryName;

        public bool IsEnabled(LogLevel logLevel) => true;

        public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception exception, Func<TState, Exception, string> formatter)
        {
            //ef core執行數據庫查詢時的categoryName為Microsoft.EntityFrameworkCore.Database.Command,日志級別為Information
            if (categoryName == "Microsoft.EntityFrameworkCore.Database.Command"
                    && logLevel == LogLevel.Information)
            {
                var logContent = formatter(state, exception);
                //TODO: 拿到日志內容想怎么玩就怎么玩吧
                Console.WriteLine();
                Console.ForegroundColor = ConsoleColor.Green;
                Console.WriteLine(logContent);
                Console.ResetColor();
            }
        }
        public IDisposable BeginScope<TState>(TState state) => null;
    }

我這里是控制台程序，在ResearchContext中稍作修改就可以了

var loggerFactory = new LoggerFactory();
                loggerFactory.AddProvider(new EFLoggerProvider());
optionsBuilder.UseSqlServer("連接字符串，可從配置文件中讀取")
                              .UseLoggerFactory(loggerFactory);

如果是web項目，可以在Startup的ConfigureService中配置

services.AddDbContext<YourDbContext>(r => {
                //使用ef core mysql 連接
                var loggerFactory = new LoggerFactory();
                loggerFactory.AddProvider(new EFLoggerProvider());
 
                r.UseSqlServer(Configuration.GetConnectionString("你的連接字符串"))
                    .UseLoggerFactory(loggerFactory);
            });

我們這里是控制台程序，Main方法中的代碼

static async Task Main(string[] args)
        {
            Console.WriteLine("Hello World!");
Students stu = new Students { StuGender = "0", StuBirthday = DateTime.Now, StuName = "CHAUVET", StuPhone = "17655889687" };
            using (var context = new ResearchContext())
            {
               var id =  await context.Students.AddAsync(stu);
                await context.SaveChangesAsync();

                var obj = await context.Students.Where(p=>p.StuName=="CHAUVET").ToListAsync();

                Console.WriteLine(obj[0].StuName);
            }
        }

效果如圖

 主要參考：https://www.cnblogs.com/hualiu0/p/10826392.html