我正在调用一个存储过程并声明一个输出参数:
CREATE PROCEDURE dbo.usp_getIsReadyForProcess
@VideoId INT ,
@val INT OUTPUT
AS
BEGIN
BEGIN TRY
BEGIN TRANSACTION
-- LOCK ROW UNTIL END OF TRANSACTION
SELECT * FROM dbo.ProcessStatus WITH (ROWLOCK, HOLDLOCK) WHERE VideoId = @VideoId
然后在整个交易过程中设置值
--If there is no row count
IF @@ROWCOUNT = 0
BEGIN
SET @val = 0
END
-- If video is already in process
ELSE IF @statusCode > 1
BEGIN
SET @val = 0
END
...... more if blocks
-- RELEASE LOCK
COMMIT TRANSACTION
END TRY
下面是获取输出参数的c#代码:
using (var db = EntityFactory.GetInstance())
{
ObjectParameter objParam = new ObjectParameter("val", typeof(int));
db.usp_getIsReadyForProcess(videoId, objParam);
return (int)objParam.Value == 1;
}
...但是无论我做什么, objParam.Value 都是空的。
所以我更深入地挖掘并发现了一个已经处理过的异常,
消息:只能在 Type.IsGenericParameter 为 true 的类型上调用方法。
我究竟做错了什么?我试过 type(bool, int32, string) .. 没有任何效果