-
新建项目
-
安装EF
-
配置数据库连接字符串
-
<connectionStrings> -
添加Ef文件夹，写入Book类，及数据上下文类MvcDbContext（继承自DbContext）
-
public class Book { public int ID { get; set; } [MaxLength(20)] public string Name { get; set; } public double Price { get; set; } }
public class MvcDbContext:DbContext { public MvcDbContext() : base("myConn") { }//传入Web.Config中连接字串名字 public DbSet Books { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder)//移除约定 让迁移的表名为单数形式，默认是以Books命名数据表 { modelBuilder.Conventions.Remove(); base.OnModelCreating(modelBuilder); } }
-
数据库迁移的几个命令 1.Enable-Migrations 自动生成数据库迁移配置文件Configuration.cs，设置允许自动迁移AutomaticMigrationsEnabled = true; 2.Update-Database -force 强制更新数据库 ** 小提示 **
- Enable-Migrations仅执行一次 *
- Update-Database不会删除原数据表中的记录 *
- Update-Database -force在缩小字段属性时用到强制转换参数 *
0：25：45
- 当视图中输入@会出现智能提示，这是因为在视图文件夹中的Web.config中添加了相应的引用。 · ·
- 视图中样式的引用其实是在App_Start/BundleConfig.cs中定义好的虚拟引用。
- 视图中引用分部视图@Html.Partial("_Menu")
- 视图启动时首先加载_ViewStart.cshtml中内容，不使用模板页可设置Layout = null;
0：50：00
namespace MvcSample.Mvc
{/// <summary>
/// view扩展，需要在Views/Web.config中更改默认pages pageBaseType="System.Web.Mvc.WebViewPage"为 "MvcSample.Mvc.MyWebViewPage" > 前台@可以提示了@Helper.HelloWerld()
/// </summary>
/// <typeparam name="TModel"></typeparam>
public abstract class MyWebViewPage<TModel> : WebViewPage<TModel>
{
public MyWebViewPage()
{
this.Helper = new MyHelper();
}
public MyHelper Helper { get; set; }
}
public class MyHelper
{
public MvcHtmlString HelloWerld()
{
return new MvcHtmlString("hello.world!");//自定义任意方法
}
}
}
通过资源、路由、过滤器、更改线程语言文化实现。生成后自动产生语言包，可删除不用 访问形式http://localhost:54325/zh-cn/book/create http://localhost:54325/en-cu/book/create
-
新建资源 属性都public 名称：BookName 值：书名 复制并改名Resources.en-us.resx名称：BookName 值：Book is Name
-
类字段约束为[Display(ResourceType = typeof(Resources), Name = "BookName")]
-
路由配置为
-
routes.MapRoute( name: "Default", url: "{lg}/{controller}/{action}/{id}", defaults: new {lg="zh-cn", controller = "Home", action = "Index", id = UrlParameter.Optional } );
-
过滤器
namespace MvcSample.Controllers
{
public class MyActionFilter : IActionFilter
{
public void OnActionExecuted(ActionExecutedContext filterContext)
{
}
public void OnActionExecuting(ActionExecutingContext filterContext)
{
var routeData = filterContext.RouteData;//获取路由数据,打断点可查看数据
string lg = filterContext.RouteData.Values["lg"].ToString();//获取lg值
Thread.CurrentThread.CurrentCulture = new System.Globalization.CultureInfo(lg);//更改线程中的语言文化
Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo(lg);//更改UI线程中的语言文化
}
}
}
- FilterConfig.cs中添加全局过滤器
filters.Add(new MyActionFilter());//添加自定义全局过滤器
1:27:30
- namespace MvcSample.Controllers { public class BookController : Controller { // GET: Book public ActionResult Index() { MvcDbContext db = new MvcDbContext(); return View(db.Books); } public ActionResult Create() { return View(); } [HttpPost] public ActionResult Create(Book book) { MvcDbContext db = new MvcDbContext(); //db.Entry(book).State = System.Data.Entity.EntityState.Added;//状态跟踪 db.Books.Add(book); db.SaveChanges(); return RedirectToAction(nameof(Index));//nameof(Index) 当Index控制器重命名时跟着重命名 } } }
** 查看数据库连接 sp_who **
数据库分区分表、复制、AlwaysOn高可用性 0:21:45
-
新建EfDemo控制台项目
-
安装EF框架
-
添加数据库连接字符串
-
新建/Models/Book类
-
namespace EfDemo.Models { public class Book { public int ID { get; set; } public string Name { get; set; } public decimal Price { get; set; } public DateTime CreateDate { get; set; } } }
-
新建映射类/Maping/BookMap
-
namespace EfDemo.Mapping { public class BookMap : EntityTypeConfiguration { public BookMap() { this.Property(b => b.Name).HasMaxLength(20); this.Property(b => b.Price).HasColumnType("money"); } } }
-
新建数据库上下文类
-
namespace EfDemo.Models { public class DemoDbContext : DbContext { public DemoDbContext() : base("demo") { } protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Conventions.Remove();//移除约定 让迁移的表名为单数形式，默认是以Books命名数据表 modelBuilder.Configurations.AddFromAssembly(Assembly.GetExecutingAssembly());//扫描当前配置的东西全加载进来，Mapping就会生效 base.OnModelCreating(modelBuilder); } public DbSet Books { get; set; } } }
-
允许数据迁移 · >Enable-Migrations · Configuration.cs
AutomaticMigrationsEnabled = true; -
数据迁移
>Updata-database
0:39:30
-
安装EntityFramework.Extended
-
新建类EfExtendedDemo/EfExtendedSample.cs
-
using EntityFramework.Extensions; using EfDemo.Models; using EntityFramework.Caching; using EntityFramework;
namespace EfDemo.EfExtendedDemo { class EfExtendedSample { public void BatchDelete()//批量删除 { DemoDbContext db = new DemoDbContext(); db.Books.Where(b => b.Price <= 100).Delete(); db.SaveChanges(); }
public void BatchUpdate()//批量更新 { DemoDbContext db = new DemoDbContext(); db.Books.Where(b => b.Price <= 100).Update(bc => new Book { Price = bc.Price + 10 }); db.SaveChanges(); } public void BatchQuery()//批量查询 { DemoDbContext db = new DemoDbContext(); //var books = db.Books.Where(b => b.Price >= 100).ToList(); //var books2 = db.Books.Where(b => b.Price <= 100).ToList(); var q1 = db.Books.Where(b => b.Price >= 100).Future();//加上 .Future()进行标记就可以在一个查询连接中执行多个查询 var q2 = db.Books.Where(b => b.Price <= 100).Future(); var books = q1.ToList(); var books2 = q2.ToList(); } public void CacheQueryResult()//使用缓存 { DemoDbContext db = new DemoDbContext(); var q1 = db.Books.Where(b => b.Price >= 100).FromCache(); var q2 = db.Books.Where(b => b.Price >= 100).FromCache(CachePolicy.WithDurationExpiration(TimeSpan.FromMinutes(10)));//10钟后过期 var q3 = db.Books.Where(b => b.Price >= 100).FromCache(tags:new[] { "book111","oldbook"});//给缓存打N个标记 CacheManager.Current.Expire("book111");//让标记的缓存过期 // Locator.Current.Register<ICacheProvider>(() =>new RedisCache());//配置一下Redis即可实现分布式缓存 } }}
··· 0:59:40
1:33:05
要下载一个老外写的文件底层操作类TransactedFile.cs
TransactedFile.Delete(@"C:\1.jpg")
1:40:44
using EfDemo.Models;
using System.Data.SqlClient;
using System.Transactions;
/// <summary>
/// EF事务示例 引用System.Transactions;
/// </summary>
namespace EfDemo.EfTransactionDemo
{
public class EfTranSample
{
public void TransactionScoptTest()//常规的用法
{
using (var tran = new TransactionScope())
{
DemoDbContext db1 = new DemoDbContext();
db1.Books.Find(1).Name = "C+++";
DemoDbContext db2 = new DemoDbContext();
db2.Books.Find(2).Name = "C++++";
db1.SaveChanges();
db2.SaveChanges();
tran.Complete();
}
}
public void Ef6TransactionTest()//EF6将语句嵌入事务
{
DemoDbContext db = new DemoDbContext();
using (var tran = db.Database.BeginTransaction())
{
try
{
string sql = "";
db.Database.ExecuteSqlCommand(sql);
db.Books.Find(1).Name = "JJJ";
db.SaveChanges();
}
catch
{
tran.Rollback();
}
}
}
public void ExistTransactionTest()//将DbContext嵌入事务
{
using (var conn = new SqlConnection("connString"))//using System.Data.SqlClient;
{
conn.Open();
using (var sqlTran = conn.BeginTransaction())
{
try
{
SqlCommand command = new SqlCommand();
command.Connection = conn;
command.Transaction = sqlTran;
command.CommandText = "sql";
command.ExecuteNonQuery();
DemoDbContext db = new DemoDbContext();
db.Database.UseTransaction(sqlTran);
db.Books.Find(1).Price = 11;
db.SaveChanges();
sqlTran.Commit();
}
catch
{
sqlTran.Rollback();
}
}
}
}
}
}
··· 1:54:50
db2.SaveChangesAsync();
1:55:30
-
{ public class ConcurrencySapmple { public void DefaultConcurrencyTest()//并发处理前提Book类加字段锁[ConcurrencyCheck]（BookMap启用字段检查this.Property(b => b.Price).IsConcurrencyToken();）或加时间戳[Timestamp]public Byte[] RowVersion { get; set; }（BookMap中启用行版本this.Property(b => b.RowVersion).IsRowVersion();） { try { DemoDbContext db1 = new DemoDbContext(); DemoDbContext db2 = new DemoDbContext();
var book1 = db1.Books.Find(1); var book2 = db2.Books.Find(1); book1.Price += 10; book1.Name = "Book1"; book2.Price += 20; book2.Name = "Book2"; db1.SaveChanges(); db2.SaveChanges(); } catch (DbUpdateConcurrencyException e)//using System.Data.Entity.Infrastructure; { e.Entries.Single().Reload();//获取没保存成功的，重新装载一下，把数据库最新版本再装载一下并执行,让并行的都得以执行，不会产生覆盖 } } }}