手动写Entity Framework 数据库上下文和Model实体

时间:2023-03-09 00:13:07
手动写Entity Framework 数据库上下文和Model实体

1、引用EF对应的程序集

使用命令安装EntityFramework包
Install-Package EntityFramework

手动写Entity Framework 数据库上下文和Model实体

Entity Framework简单目录:

手动写Entity Framework 数据库上下文和Model实体

1.context数据库上下文class:

using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Linq;
using System.Web; namespace ClothMvcApp.EF
{
public class ClothDBContext: DbContext, IDisposable
{
public ClothDBContext()
: base("name=ClothDBContext")
{
} protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
} public DbSet<News> News { get; set; }
public DbSet<Product> Product { get; set; }
public DbSet<SysUser> SysUser { get; set; } public DbSet<Brand> Brand { get; set; } public DbSet<ImageInfo> ImageInfo { get; set; } public DbSet<Contact> Contact { get; set; }
}
}

2.Model实体类:

添加所需程序集:

Install-Package System.ComponentModel.Annotations

如下图:

手动写Entity Framework 数据库上下文和Model实体

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Web; namespace ClothMvcApp.EF
{
[Table("Brand")]
public class Brand
{
[Column("Id")]
public Guid Id { get; set; } [Column("Content")]
public string Content { get; set; } [Column("Picture")]
public string Picture { get; set; } [Column("CreateTime")]
public DateTime CreateTime { get; set; }
}
}

有外键字段Model:

using System;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema; namespace Lemon.Media.Entities
{
/// <summary>
/// 渠道应用
/// </summary>
[Table("Channel_Apps")]
public class ChannelApp
{
[Key, Column("Id")]
public Guid Id { get; set; } /// <summary>
/// 渠道ID(主要指物业)
/// </summary>
[Column("ChannelId")]
public int ChannelId { get; set; } /// <summary>
/// 是否由H5承载实现
/// </summary>
[Column("IsH5")]
public bool IsH5 { get; set; } /// <summary>
/// App应用唯一标识
/// </summary>
[Column("AppKey")]
public string AppKey { get; set; } /// <summary>
/// 添加时间
/// </summary>
[Column("AddTime")]
public DateTime AddTime { get; set; } /// <summary>
/// 是否删除
/// </summary>
[Column("IsDel")]
public bool IsDel { get; set; } /// <summary>
/// 是否需要PPTV
/// </summary>
[Column("HasPPTV")]
public bool HasPPTV { get; set; } /// <summary>
/// 渠道
/// </summary>
[ForeignKey("ChannelId")]
public virtual Channel Channel { get; set; }
}
}

3.web.config 数据库连接字符串:

<connectionStrings>

    <add name="ClothDBContext" connectionString="Data Source=.;Initial Catalog=ClothDB;User ID=sa;Password=123456;Pooling=true;" providerName="System.Data.SqlClient" />
</connectionStrings>

4.简单的调用方式:

using (var context = new ClothDBEntities())
{
context.ImageInfo.Where(c => c.Cate == "banner").OrderByDescending(c => c.CreateTime).Take().ToList();
}

ps:卸载nuget包:

Uninstall-Package System.ComponentModel.Annotations