Entity Framework实例

Bertha 。 2021-11-26 16:46 272阅读 0赞

1、数据定义

Book表

using System;  
using System.Data.Objects;  
using System.Data.Objects.DataClasses;  
using System.Data.EntityClient;  
using System.ComponentModel;  
using System.Data.Entity;  
using System.ComponentModel.DataAnnotations;

namespace EFTest.Models.Part2  
\{  
    \[Table("Book")\]  
    public class Book  
    \{  
        \[Key\]  
        public int BookId \{ get; set;\}  
        public string BookName \{ get; set; \}  
        public int CatalogId \{ get; set; \}

public virtual Catalog catalog \{ get; set; \}  
    \}

Catalog表

namespace EFTest.Models.Part2  
\{  
    \[Table("Catalog")\]  
    public class Catalog  
    \{  
        \[Key\]  
        public int CatalogId \{ get; set; \}  
        public string Name \{ get; set; \}

\}  
\}

2.数据访问层

using System;  
using System.Data.Objects;  
using System.Data.Objects.DataClasses;  
using System.Data.EntityClient;  
using System.Collections.Generic;  
using System.Linq;  
using System.Web;  
using System.Data.Entity;

namespace EFTest.Models.Part2  
\{  
     
     
    public partial class DbContextFactory : DbContext  
    \{  
        public DbSet<Book> Books \{ get; set; \}  
        public DbSet<Catalog> Catalogs \{ get; set; \}   
    \}  
\}

web.config加入以下配置

</connectionStrings>

数据增加、删除、修改

Book book = new Book  
\{  
BookName = "kenny",  
CatalogId = 3  
\};  
using (var context = new DbContextFactory())  
\{  
context.Books.Add(book);  
context.SaveChanges();//增加

book = context.Books.Find(2);  
context.Books.Remove(book);//删除  
context.SaveChanges();

book = context.Books.Find(2);  
book.BookName = "ss";  
context.SaveChanges();//修改

转载于:https://www.cnblogs.com/kenny999/archive/2011/12/24/2300352.html