Entity Framework Code First Using One column as Primary Key and another as Auto Increment Column

Question

I have a class named Sale

public class Sale {     public int Id { get; set; }     public string TrNo { get; set; }     public DateTime Date { get; set; }     public int CustomerID { get; set; }      public ObservableCollection<SaleDetail> SaleDetails { get; set; } } 

And in the database, I want the Id as the Auto Increment column and the TrNo as the Primary Key column.

Please tell me how to do this using EF5 code first.

Thanks.

Answer 1

You can also do this with Data Annotations:

public class Sale {     [DatabaseGenerated(DatabaseGeneratedOption.Identity)]     public int Id { get; set; }      [Key]     public string TrNo { get; set; }      public DateTime Date { get; set; }     public int CustomerID { get; set; }      public ObservableCollection<SaleDetail> SaleDetails { get; set; } } 

Answer 2

I believe you can do this using Fluent API

protected override void OnModelCreating(DbModelBuilder modelBuilder) {     modelBuilder.Entity<Sale>().Property(a => a.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);     modelBuilder.Entity<Sale>().Property(a => a.TrNo).HasKey(b => b.TrNo); }