3

I have a simple database:

ARTICLE
----------
ArticleId (PK),
ArticleTitle
..other stuff...

USER-ARTICLE
------------
ArchiveId (PK),
UserId,
ArticleId
..other stuff...

The articleId's are foreign keys.

I want to be able to delete a user article row by UserArticleId using the following code,

UserArticle myobjtodelete = PersonalArchiveDb.UserArticles.Single(ua => ua.ArchiveId == 3);
PersonalArchiveDb.UserArticles.DeleteOnSubmit(myobjtodelete);
PersonalArchiveDb.SubmitChanges();

(Yes I'm aware I can do the statement inside the delete rather than retrieving the object, it was for debugging purposes to make sure the object definitely exists - it does.)

When the debugger hits the SubmitChanges() line, I get a runtime error:

Specified cast is not valid.

Here is the stack trace,

at System.Data.Linq.IdentityManager .StandardIdentityManager .SingleKeyManager`2.TryCreateKeyFromValues(Object[] values, V& v) at System.Data.Linq.IdentityManager.StandardIdentityManager.IdentityCache`2.Find(Object[] keyValues) at System.Data.Linq.IdentityManager.StandardIdentityManager.Find(MetaType type, Object[] keyValues) at System.Data.Linq.CommonDataServices.GetCachedObject(MetaType type, Object[] keyValues) at System.Data.Linq.ChangeProcessor.GetOtherItem(MetaAssociation assoc, Object instance) at System.Data.Linq.ChangeProcessor.BuildEdgeMaps() at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode) at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode)
at System.Data.Linq.DataContext.SubmitChanges() at Driver_SOC_ASO.Controls.PersonalArchive.ArchiveListing.grdArchive_RowDeleting(Object sender, GridViewDeleteEventArgs e) in C:\work\Driver.Net\Driver-SOC-ASO\Driver-SOC-ASO\Controls\PersonalArchive\ArchiveListing.ascx.cs:line 78 at System.Web.UI.WebControls.GridView.OnRowDeleting(GridViewDeleteEventArgs e) at System.Web.UI.WebControls.GridView.HandleDelete(GridViewRow row, Int32 rowIndex) at System.Web.UI.WebControls.GridView.HandleEvent(EventArgs e, Boolean causesValidation, String validationGroup) at System.Web.UI.WebControls.GridView.RaisePostBackEvent(String eventArgument) at System.Web.UI.WebControls.GridView.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

I am at a loss, any ideas?

4

3 回答 3

1

这可能是这个bug的一个例子,微软称它在 .NET 4.0 中已修复。

于 2009-06-04T00:01:23.600 回答
0

尝试设置 ON CASCADE DELETE 为ArticleId

于 2009-04-05T03:39:21.233 回答
0

在您的 dbml 中,检查是否存在不正确的关联黑白文章和用户文章。

于 2010-03-10T21:46:48.917 回答