sql server - Writing AutoIncrement for primary key in CodeFirst -

i using codefirst in project. 1 of things learning how can design tables first writing classes. question - how can classify primary key [key] id, auto increment field. when record created (or row in table) primary key auto generated. how do in codefirst while writing class definition. help.

 public class newtable {       //looking [autoincrement][key] id field etc...     [key]     public int id { get; set; }      [required(errormessage = "title required")]     [displayname("title")]     public string title { get; set; }  } 

a string auto increment? that's not gonna work.

use int instead, , pk identity column default. don't need [key] attribute either; ef infer because property called id.