database context dependency injection

AspNetFrameworkMVC/AspNetCoreMVC/Controllers/UserController.cs

@@ -8,19 +8,24 @@ namespace AspNetCoreMVC.Controllers
     [Route("api/user")] // 컨트롤러 전체 라우터 설정
     public class UserController : Controller
     {
+        private ModelDbContext _db;
+
+        public UserController(ModelDbContext db)
+        {
+            _db = db;
+        }
+
         [HttpGet("{id}")]
         public JsonResult GetUser(int id)
         {
-            var db = new ModelDbContext();
+            var user = _db.Users.SingleOrDefault(u => u.Id == id);
-            var user = db.Users.SingleOrDefault(u => u.Id == id);
             return Json(user);
         }
 
         [HttpGet("v2/{id}")]
         public IActionResult GetUser2(int id)
         {
-            var db = new ModelDbContext();
+            var user = _db.Users.SingleOrDefault(u => u.Id == id);
-            var user = db.Users.SingleOrDefault(u => u.Id == id);
             if (user == null)
                 return BadRequest("No data found");
 
@@ -32,12 +37,11 @@ namespace AspNetCoreMVC.Controllers
         {
             try
             {
-                var db = new ModelDbContext();
-
                 if (!ModelState.IsValid)
                     return Json(false);
 
-                db.Users.Add(user);
+                _db.Users.Add(user);
+                _db.SaveChanges();
                 return Json(true);
             }
             catch (Exception ex)

AspNetFrameworkMVC/AspNetCoreMVC/DataContext/ModelDbContext.cs

@@ -9,10 +9,9 @@ namespace AspNetCoreMVC.DataContext
         public DbSet<Person> Persons { get; set; }
         public DbSet<User> Users { get; set; }
 
-        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
+        public ModelDbContext(DbContextOptions<ModelDbContext> option) : base(option)
         {
-            string connectionString = "server=peacecloud.synology.me,21433;database=study;uid=study;pwd=Study1234";
+            
-            optionsBuilder.UseSqlServer(connectionString);
         }
     }
 }

AspNetFrameworkMVC/AspNetCoreMVC/Program.cs

@@ -1,3 +1,6 @@
+using AspNetCoreMVC.DataContext;
+using Microsoft.EntityFrameworkCore;
+
 namespace AspNetCoreMVC
 {
 	public class Program
@@ -9,6 +12,9 @@ namespace AspNetCoreMVC
 			// Add services to the container.
 			builder.Services.AddControllersWithViews();
 
+			// service registration
+			builder.Services.AddDbContext<ModelDbContext>(option => option.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection")));
+
 			var app = builder.Build();
 
 			// Configure the HTTP request pipeline.