我有一个存储过程,它返回0或1,具体取决于我的数据库中是否存在指定的电子邮件地址:
CREATE PROCEDURE [DatabaseSchema].[EmailAddressIsDuplicate] (@emailAddress nvarchar(255)) AS BEGIN SET NOCOUNT ON; IF EXISTS( SELECT * FROM [DatabaseSchema].[EmailUpdatesRegistrant] WHERE EmailAddress = @emailAddress ) RETURN 1 ELSE RETURN 0 RETURN 0 END GO
我试图从Entity Framework 6数据库上下文中获取此存储过程的结果:
using (DatabaseContext dbContext = new DatabaseContext()) { ObjectParameter param = new ObjectParameter("emailAddress", typeof(bool)); var result = dbContext.EmailAddressIsDuplicate(emailAddress); }
我收到很多错误.
错误#1:使用上面的代码,var结果始终设置为-1.
错误#2:我尝试导航到编辑函数导入并将返回集合设置为布尔标量值.这会引发以下错误:
The data reader returned by the store data provider does not have enough columns for the query requested.
错误#3:我回去并将编辑功能导入返回值设置为无.然后我尝试了以下代码:
using (DatabaseContext dbContext = new DatabaseContext()) { var p = new SqlParameter("@emailAddress", emailAddress); var result = dbContext.Database.SqlQuery<bool>("DatabaseSchema.EmailAddressIsDuplicate", p); }没有立即错误抛出,但我不知道我是否可以从var结果中获取有用的数据.尝试将结果转换为bool会引发以下错误:
Cannot convert type ‘System.Data.Entity.Infrastructure.DbRawSqlQuery’ to ‘bool’
关于如何查看此存储过程(0或1)的结果的任何想法?
您可以尝试在存储过程签名中添加输出参数(@result):CREATE PROCEDURE [DatabaseSchema].[EmailAddressIsDuplicate] (@emailAddress nvarchar(255), @result bit out) AS BEGIN SET NOCOUNT ON; IF EXISTS(SELECT * FROM [DatabaseSchema].[EmailUpdatesRegistrant] WHERE EmailAddress = @emailAddress) SET @result = 1 ELSE SET @result = 0 RETURN @result END GO(您必须相应地重新定义您的EF模型函数定义)
using (DatabaseContext dbContext = new DatabaseContext()) { ObjectParameter isDuplicate = new ObjectParameter("isDuplicate", typeof(bool)); var result = dbContext.EmailAddressIsDuplicate(emailAddress, isDuplicate); bool emailIsDuplicate = (bool)isDuplicate.Value;. }如果要使用out参数直接调用存储过程,可以遵循以下建议:
Database.SqlQuery calling stored procedure that has multiple output parameters查看更多关于在C#中无法使用Entity Framework 6获取存储过程结果的详细内容...
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