通过 MVC 5 使用 Entity Framework 6 Code First （2）
https://docs.microsoft.com/zh-cn/aspnet/mvc/overview/getting-started/getting-started-with-ef-using-mvc/
SQL Server (Full Editions) Connection String Examples
PM> Install-Package EntityFramework
PM> update-database 
安装 Entity Framework 6
-
从工具菜单中，选择NuGet 包管理器，然后选择程序包管理器控制台。
-
在中程序包管理器控制台窗口中，输入以下命令：
PM> Install-Package EntityFramework 正在尝试收集与目标为“.NETFramework,Version=v4.7.2”的项目“ContosoUniversity”有关的包“EntityFramework.6.2.0”的依赖项信息 收集依赖项信息花费时间 46.61 ms 正在尝试解析程序包“EntityFramework.6.2.0”的依赖项，DependencyBehavior 为“Lowest” 解析依赖项信息花费时间 0 ms 正在解析操作以安装程序包“EntityFramework.6.2.0” 已解析操作以安装程序包“EntityFramework.6.2.0” 从“nuget.org”检索包“EntityFramework 6.2.0” 正在将程序包“EntityFramework.6.2.0”添加到文件夹“D:\csharp-demo\ContosoUniversity\packages” 已将程序包“EntityFramework.6.2.0”添加到文件夹“D:\csharp-demo\ContosoUniversity\packages” 已将程序包“EntityFramework.6.2.0”添加到“packages.config” 正在执行脚本文件“D:\csharp-demo\ContosoUniversity\packages\EntityFramework.6.2.0\tools\init.ps1” 正在执行脚本文件“D:\csharp-demo\ContosoUniversity\packages\EntityFramework.6.2.0\tools\install.ps1” Type 'get-help EntityFramework' to see all available Entity Framework commands. 已将“EntityFramework 6.2.0”成功安装到 ContosoUniversity 执行 nuget 操作花费时间 3.63 sec 已用时间: 00:00:05.1479976 PM>views/shared\_Layout.cshtml：
@ViewBag.Title - Contoso University
@Styles.Render("~/Content/css")
@Scripts.Render("~/bundles/modernizr")
@RenderBody()
@Scripts.Render("~/bundles/jquery")
@Scripts.Render("~/bundles/bootstrap")
@RenderSection("scripts", required: false)
Views\Home\Index.cshtml
@{
ViewBag.Title = "Home Page";
}
Contoso University
ASP.NET is a free web framework for building great Web sites and Web applications using HTML, CSS and JavaScript.
Welcome to Contoso University
Contoso University is a sample application that
demonstrates how to use Entity Framework 6 in an
ASP.NET MVC 5 web application.
Get more libraries
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using ContosoUniversity.Models;
using System.Data.Entity;
using System.Data.Entity.ModelConfiguration.Conventions;
namespace ContosoUniversity.DAL
{
public class SchoolContext : DbContext
{
public SchoolContext() : base("SchoolContext")
{
}
public DbSet Students { get; set; }
public DbSet Enrollments { get; set; }
public DbSet Courses { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Conventions.Remove();
}
}
} using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data.Entity;
using ContosoUniversity.Models;
namespace ContosoUniversity.DAL
{
public class SchoolInitializer : System.Data.Entity.DropCreateDatabaseIfModelChanges
{
protected override void Seed(SchoolContext context)
{
var students = new List
{
new Student{FirstMidName="Carson",LastName="Alexander",EnrollmentDate=DateTime.Parse("2005-09-01")},
new Student{FirstMidName="Meredith",LastName="Alonso",EnrollmentDate=DateTime.Parse("2002-09-01")},
new Student{FirstMidName="Arturo",LastName="Anand",EnrollmentDate=DateTime.Parse("2003-09-01")},
new Student{FirstMidName="Gytis",LastName="Barzdukas",EnrollmentDate=DateTime.Parse("2002-09-01")},
new Student{FirstMidName="Yan",LastName="Li",EnrollmentDate=DateTime.Parse("2002-09-01")},
new Student{FirstMidName="Peggy",LastName="Justice",EnrollmentDate=DateTime.Parse("2001-09-01")},
new Student{FirstMidName="Laura",LastName="Norman",EnrollmentDate=DateTime.Parse("2003-09-01")},
new Student{FirstMidName="Nino",LastName="Olivetto",EnrollmentDate=DateTime.Parse("2005-09-01")}
};
students.ForEach(s => context.Students.Add(s));
context.SaveChanges();
var courses = new List
{
new Course{CourseID=1050,Title="Chemistry",Credits=3,},
new Course{CourseID=4022,Title="Microeconomics",Credits=3,},
new Course{CourseID=4041,Title="Macroeconomics",Credits=3,},
new Course{CourseID=1045,Title="Calculus",Credits=4,},
new Course{CourseID=3141,Title="Trigonometry",Credits=4,},
new Course{CourseID=2021,Title="Composition",Credits=3,},
new Course{CourseID=2042,Title="Literature",Credits=4,}
};
courses.ForEach(s => context.Courses.Add(s));
context.SaveChanges();
var enrollments = new List
{
new Enrollment{StudentID=1,CourseID=1050,Grade=Grade.A},
new Enrollment{StudentID=1,CourseID=4022,Grade=Grade.C},
new Enrollment{StudentID=1,CourseID=4041,Grade=Grade.B},
new Enrollment{StudentID=2,CourseID=1045,Grade=Grade.B},
new Enrollment{StudentID=2,CourseID=3141,Grade=Grade.F},
new Enrollment{StudentID=2,CourseID=2021,Grade=Grade.F},
new Enrollment{StudentID=3,CourseID=1050},
new Enrollment{StudentID=4,CourseID=1050,},
new Enrollment{StudentID=4,CourseID=4022,Grade=Grade.F},
new Enrollment{StudentID=5,CourseID=4041,Grade=Grade.C},
new Enrollment{StudentID=6,CourseID=1045},
new Enrollment{StudentID=7,CourseID=3141,Grade=Grade.A},
};
enrollments.ForEach(s => context.Enrollments.Add(s));
context.SaveChanges();
}
}
} Web.config
创建一个学生控制器和视图
现在将创建一个用于显示数据 web 页。 自动请求数据的过程将触发创建数据库。 您将首先创建一个新的控制器。 但这样做之前，请生成项目以使模型和上下文类可用于 MVC 控制器基架。
-
右键单击控制器中的文件夹解决方案资源管理器，选择添加，然后单击新基架项。
-
在中添加基架对话框中，选择包含的 MVC 5 控制器视图，使用实体框架，然后选择添加。
在中添加控制器对话框中，进行以下选择，然后选择添加:
-
模型类：Student (ContosoUniversity.Models)。 （如果看不到下拉列表中的此选项，生成项目，然后重试。）
-
数据上下文类： SchoolContext (ContosoUniversity.DAL)。
-
控制器名称： StudentController (不 StudentsController)。
-
保留其他字段的默认值。
看看生成的数据库关系图，我们可以使用数据库表及其关系图自动生成代码
USE [SchoolContext]
GO
/****** Object: Table [dbo].[__MigrationHistory] Script Date: 2018/11/22 13:40:49 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_PADDING ON
GO
CREATE TABLE [dbo].[__MigrationHistory](
[MigrationId] [nvarchar](150) NOT NULL,
[ContextKey] [nvarchar](300) NOT NULL,
[Model] [varbinary](max) NOT NULL,
[ProductVersion] [nvarchar](32) NOT NULL,
CONSTRAINT [PK_dbo.__MigrationHistory] PRIMARY KEY CLUSTERED
(
[MigrationId] ASC,
[ContextKey] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
SET ANSI_PADDING OFF
GO
/****** Object: Table [dbo].[Course] Script Date: 2018/11/22 13:40:49 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Course](
[CourseID] [int] NOT NULL,
[Title] [nvarchar](max) NULL,
[Credits] [int] NOT NULL,
CONSTRAINT [PK_dbo.Course] PRIMARY KEY CLUSTERED
(
[CourseID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
/****** Object: Table [dbo].[Enrollment] Script Date: 2018/11/22 13:40:49 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Enrollment](
[EnrollmentID] [int] IDENTITY(1,1) NOT NULL,
[CourseID] [int] NOT NULL,
[StudentID] [int] NOT NULL,
[Grade] [int] NULL,
CONSTRAINT [PK_dbo.Enrollment] PRIMARY KEY CLUSTERED
(
[EnrollmentID] 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
/****** Object: Table [dbo].[Student] Script Date: 2018/11/22 13:40:49 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Student](
[ID] [int] IDENTITY(1,1) NOT NULL,
[LastName] [nvarchar](max) NULL,
[FirstMidName] [nvarchar](max) NULL,
[EnrollmentDate] [datetime] NOT NULL,
CONSTRAINT [PK_dbo.Student] PRIMARY KEY CLUSTERED
(
[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] TEXTIMAGE_ON [PRIMARY]
GO
ALTER TABLE [dbo].[Enrollment] WITH CHECK ADD CONSTRAINT [FK_dbo.Enrollment_dbo.Course_CourseID] FOREIGN KEY([CourseID])
REFERENCES [dbo].[Course] ([CourseID])
ON DELETE CASCADE
GO
ALTER TABLE [dbo].[Enrollment] CHECK CONSTRAINT [FK_dbo.Enrollment_dbo.Course_CourseID]
GO
ALTER TABLE [dbo].[Enrollment] WITH CHECK ADD CONSTRAINT [FK_dbo.Enrollment_dbo.Student_StudentID] FOREIGN KEY([StudentID])
REFERENCES [dbo].[Student] ([ID])
ON DELETE CASCADE
GO
ALTER TABLE [dbo].[Enrollment] CHECK CONSTRAINT [FK_dbo.Enrollment_dbo.Student_StudentID]
GO