如何使用 Entity Framework 6 在 ID 列中保存自定义值

Question

我正在使用代码优先方法，我不知道如何将自定义 ID 传递到 ID 列每当我尝试传递 id 时，它都会显示以下错误：

Can't insert null to table Orders.ID Insert fails

public class Order 
{       
    [Key]
    public int  ID { get; set; } // I WANT THIS COLUMN SHOULD BE SAVED AS "10001,10002,10003" INSTEAD OF "1,2,3,4"
    public string CustomerID { get; set; }
    public string CustomerName { get; set; }
    public string CustomerEmail { get; set; }

    public virtual List<OrderItem> OrderItems { get; set; }
    
    public virtual List<OrderHistory> OrderHistory { get; set; }
}

public class OrderHistory 
{
   
    public int OrderID { get; set; }
    public int OrderStatus { get; set; }
    public string Note { get; set; }
}

public class OrderItem 
{        
    public int OrderID { get; set; }

    [NotMapped]
    public string ProductName { get; set; }
    public int ProductID { get; set; }
  
    public virtual Product Product { get; set; }

    /// <summary>
    /// Item Price is in Order Item because we can have a scenerio where we might charge less or greater than the Product Price.
    /// </summary>
    public decimal ItemPrice { get; set; }

    public int Quantity { get; set; }
}

EDIT-2

添加 ID 后，它现在抛出另一个错误列名称无效 'ID' 列名称无效 'ID'

 [Key]
 [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
 public int ID { get; set; }

Answer 1

考虑到您的情况，您可以通过以下方式实施。当你 add migration command 时，我已经解决了使用这个命令的问题，在此之前你可以像下面这样添加这个

 migrationBuilder.Sql("DBCC CHECKIDENT ('Order ', RESEED, 10001)");

虽然您可以为非主键列添加预期的序列，但到目前为止我已经测试它不适用于主键列，因为迁移总是添加此命令。哪个强制执行SQL server to take the controls of identity

.Annotation("SqlServer:ValueGenerationStrategy", SqlServerValueGenerationStrategy.IdentityColumn)

Note: So we need to add above mensioned command to override it. Which implement the custom identity as we want.

希望它能帮助您实现目标。

如何使用 Entity Framework 6 在 ID 列中保存自定义值

How to save custom value in ID column using Entity Framework 6

c#

ef-code-first

entity-framework-6

entity-framework-core

asp.net-core