Entity Framework basics-Article 6 (Code First), entityframework

Entity Framework basics-Article 6 (Code First), entityframework

If you don't need to talk about it, create a project directly below:

1. Create a console application

Public class UserInfo

    {

public UserInfo()        {            OrderInfo = new HashSet<OrderInfo>();        }

        [Key]

Public int UserID {get; set;} // primary key

Public string UserName {get; set;} public virtual ICollection <OrderInfo> OrderInfo {get; set;} // navigation attribute}

public class OrderInfo    {        [Key]

public int ID { get; set; }        public string OrderContent { get; set; }        public virtual UserInfo UserInfo { get; set; }          }

Add Key reference:

Public class CodeFirstDbContext: DbContext {public CodeFirstDbContext (): base ("name = ModelFirstKey") {} protected override void OnModelCreating (DbModelBuilder modelBuilder) {modelBuilder. conventions. remove <PluralizingTableNameConvention> (); // Remove the complex table name s} public DbSet <UserInfo> UserInfo {get; set;} public DbSet <OrderInfo> OrderInfo {get; set ;}}

5. Configure App. config

<connectionStrings>    <add name="ModelFirstKey" connectionString="server=.;uid=sa;pwd=123;database=CodeFirstDemoDB;" providerName="System.Data.SqlClient"/>  </connectionStrings>

 

6. add data

static void Main(string[] args){              

    using(CodeFirstDbContext dbContext = new CodeFirstDbContext())

    {       dbContext.Database.CreateIfNotExists();       UserInfo userInfo = new UserInfo();       userInfo.UserName = "xiaoyang";       dbContext.UserInfo.Add(userInfo);       dbContext.SaveChanges();       Console.ReadKey();

    }}

Run to automatically generate databases and tables: