Asp. NET using Entityframeworkcore codefrist

1, first download the corresponding Microsoft official. NET Core SDK and runtime (Https://www.microsoft.com/net/download/core) according to individual needs

2, create an ASP. NET Core Project

3, create entity entities, users and roles

    public class User    {public        int Id {get; set;}        <summary>///Role ID///        </summary> public        int Roleid {get; set;}        Public virtual role Role {get; set;}        <summary>///state//        </summary> public        int status {get; set;}        <summary>///Login name///        </summary> public        string Login {get; set;}        <summary>///Login password///        </summary> public        string Pwd {get; set;}    }

    public class Role    {public        int Id {get; set;}        <summary>///Role name///        </summary> Public        string name {get; set;}        <summary>////        for multiple users of a role///        </summary> public        virtual icollection<user> users {get ; Set }    }

4, create DbContext

    public class Efdbcontext:dbcontext {public efdbcontext (dbcontextoptions<efdbcontext> options): Base        (options)        {} public dbset<role> Roles {get; set;}        Public dbset<user> Users {get; set;}            protected override void Onmodelcreating (ModelBuilder ModelBuilder) {Role (ModelBuilder);        User (ModelBuilder); } private void User (ModelBuilder ModelBuilder) {var userbuilder = Modelbuilder.entity<user&gt ;().            ToTable ("User"); Properties userbuilder.property (t = t.id).            Valuegeneratedonadd (); Userbuilder.property (t = t.roleid).            IsRequired (); Userbuilder.property (t = t.status).            IsRequired (); Userbuilder.property (t = t.login). IsRequired ().            Hasmaxlength (30); Userbuilder.property (t = t.pwd). IsRequired ().            Hasmaxlength (60);        Primary Key userbuilder.haskey (t = t.id);    Index userbuilder.hasindex (t = t.login); Relationships Userbuilder.hasone (t = t.role). Withmany (t = t.users).        Hasforeignkey (t = t.roleid); } private void Role (ModelBuilder ModelBuilder) {var rolebuilder = Modelbuilder.entity<role&gt ;().            ToTable ("Role"); Properties rolebuilder.property (t = t.id).            Valuegeneratedonadd (); Rolebuilder.property (t = t.name). IsRequired ().            Hasmaxlength (30);        Primary Key rolebuilder.haskey (t = t.id); }    }

5, create Dbinitializer, to create initial data

    public class Dbinitializer    {public        async static Task InitData (Efdbcontext context)        {            if (context. Database! = null && context. Database.ensurecreated ())            {                //Role Configuration                context. Roles.addrange (new role[]                {                    new role {name= "Super admin"},                    new role {name= "Administrator"}                );                Default User                context. Users.addrange (new user[]                {                    New user {roleid=1, login= "Administrator", pwd= "111111"},                    new user {Roleid =2, login= "admin", pwd= "111111"}                );                Await the context. Savechangesasync ();            }        }

6, modify the Startup class method

Add the following code to the Configureservices

dbcontextservices.adddbcontext<efdbcontext> (options = options. Usesqlserver (configuration.getconnectionstring ("defaultconnection"));

Adding within the Configure method

        Public async void Configure (Iapplicationbuilder app, Ihostingenvironment env, iloggerfactory loggerfactory)        {            Loggerfactory.addconsole (Configuration.getsection ("Logging"));            Loggerfactory.adddebug ();            App. Usemvc ();            Await Dbinitializer.initdata (app. Applicationservices.getservice<efdbcontext> ());        }

7, modify Appsettings.json

{"  ConnectionStrings": {    "defaultconnection": "Data source=.;i Nitial catalog=lnicecore;integrated security=sspi; "  },  " Logging ": {    " includescopes ": false,    " LogLevel ": {      " Default ":" Debug ",      " System ":" Information ",      " Microsoft ":" Information "}}  }

8, run the program, view the results