Vic*_*tor 9 c# entity-framework-core
当我在ASP.NET Core项目中从Entity Framework Core(v2.0)执行SQL Server存储过程时,我得到以下异常:
InvalidOperationException:无法找到CLR类型'Int32 []'的关系类型的映射
SQL Server存储过程代码如下所示:
CREATE PROCEDURE [dbo].[sp-UpdateProductOrderAndStock]
@customerOrderID INT,
@qty INT
AS
DECLARE @customerProductID INT
SET @customerProductID = (SELECT CustomerProductID
FROM dbo.CustomerOrder
WHERE ID = @customerOrderID)
SET NOCOUNT ON;
UPDATE dbo.CustomerOrder
SET CompletedQty = CompletedQty + @qty
WHERE ID = @customerOrderID;
UPDATE dbo.CProductStation
SET Qty = Qty - @qty
WHERE CustomerProductID = @customerProductID AND StationNo = 0;
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ASP.NET Core数据模型如下:
public class CustomerProductDelivery
{
public int ID { get; set; }
public int CustomerOrderID { get; set; }
public DateTime DeliveryDate { get; set; }
public string DeliveryNo { get; set; }
public int DeliveryQty { get; set; }
public CustomerOrder CustomerOrder { get; set; }
}
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ASP.net核心控制器代码执行存储过程:
_context.Database.ExecuteSqlCommand("sp-UpdateProductOrderAndStock @p0, @p1", parameters: new[] { customerProductDelivery.CustomerOrderID,customerProductDelivery.DeliveryQty });
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Iva*_*oev 13
你陷入了一个典型的params object[]陷阱.
首先,让我们看一下表达式的类型
var parameters = new[] { customerProductDelivery.CustomerOrderID,customerProductDelivery.DeliveryQty }
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由于两个元素都是类型int,因此推断类型是int[].
现在,有2个ExecuteSqlCommand方法重载,允许您分别传递参数 - 一个接收params object[]和第二个接收IEnumerable<object>.
虽然IEnumerable<T>是协变的,但协方差对值类型不起作用,因此IEnumerable<int>不能被视为IEnumerable<object>,因此第二个重载不匹配.
因此唯一有效的重载是接收params object[].但是由于int[]无法转换object[],编译器将其视为单一 object,这就像是一样new object[] { parameters }.
下一个效果是EF方法接收int[]并生成有问题的异常.
话虽如此,它可以通过多种方式得到修复.
一种是new [] { }从调用中删除,这是params object[]构造的整个想法:
_context.Database.ExecuteSqlCommand(
"Update_ProductOrderAndStock @p0, @p1", customerProductDelivery.CustomerOrderID, customerProductDelivery.DeliveryQty);
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另一种是new []用显式替换new object[].
还有一个是在FromSql和ExecuteSqlCommand中使用EF Core引入的字符串插值:
_context.Database.ExecuteSqlCommand(
$"Update_ProductOrderAndStock {customerProductDelivery.CustomerOrderID}, {customerProductDelivery.DeliveryQty}");
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请更新代码
从
_context.Database.ExecuteSqlCommand(
"sp_UpdateProductOrderAndStock @p0, @p1", parameters:
new[]
{
customerProductDelivery.CustomerOrderID,customerProductDelivery.DeliveryQty
});
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到
List<SqlParameter> pc = new List<SqlParameter>
{
new SqlParameter("@customerOrderID", customerProductDelivery.CustomerOrderI),
new SqlParameter("@qty", customerProductDelivery.DeliveryQty)
}
_context.Database.ExecuteSqlCommand("sp_UpdateProductOrderAndStock @customerOrderID, @qty", pc.ToArray());
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