EF add data when the insert failed id can not be null, but we have the value assigned.

System.Data.SqlClient.SqlException: cannot insert value NULL into column ‘ID’, table ‘dbo.Sys_MenuBasis’; column is not allowed to have NULL value.

This is caused by ef treating data with id attribute as self-adding id

Solution:

public class ERPContext : DbContext
{
public ERPContext():base(“ERPContext”)
{
}
public IDbSet<Sys_MenuBasis> Sys_MenuBasis { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Sys_MenuBasis>().Property(p => p.ID).HasDatabaseGeneratedOption(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.None);
}
}

Or add to the entity primary key attribute

public class Sys_MenuBasis
{

[System.ComponentModel.DataAnnotations.Schema.DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.None)]
public long ID { get; set; }

}

Done!