Code配置DbConfiguration

public class SQLiteConfiguration : DbConfiguration {
    public SQLiteConfiguration() {
        SetProviderFactory("System.Data.SQLite", SQLiteFactory.Instance);
        SetProviderFactory("System.Data.SQLite.EF6", SQLiteProviderFactory.Instance);
        Type t = Type.GetType(
                    "System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6");
        FieldInfo fi = t.GetField("Instance", BindingFlags.NonPublic | BindingFlags.Static);
        SetProviderServices("System.Data.SQLite", (DbProviderServices)fi.GetValue(null));
    }
}

[DbConfigurationType(typeof(SQLiteConfiguration))]
public class AdminContext : DbContext {
    public AdminContext() : base("name=AdminContext") { }

    public AdminContext(DbConnection db) : base(db, false) { }

    public DbSet<User> User { set; get; }
}