使用EF模型数据库不使用updateModel进行更新

时间:2012-03-09 05:09:57

标签: vb.net asp.net-mvc-3 entity-framework

使用EF的MVC 3,VB.NET,RAZOR应用程序。我在post函数中遇到问题,数据库根本没有更新...在db.savechanges()处使用break我看一下变量,所有正确的信息都包含在UpdateModel()部分中。但是没有骰子代码执行并且没有返回错误所以看起来都很好但是当我查看数据库表时它根本没有被更改,所有旧值仍然存在。函数如下:

   <AcceptVerbs(HttpVerbs.Post)>
    Function EditCourse(ByVal _eCourse As cours) As ActionResult
        Dim id As Integer = _eCourse.course_id

            Dim _filename As String = String.Empty
            Dim _guid As String = String.Empty

            Dim _count As Integer = 0
            Dim _courseFiles As cours = db.courses.Where(Function(f) f.course_ref = _eCourse.course_ref).First

            Dim _file1 As String = _courseFiles.handoutFile1
            Dim _file2 As String = _courseFiles.handoutFile2
            Dim _file3 As String = _courseFiles.handoutFile3
            Dim _file4 As String = _courseFiles.handoutFile4
            Dim _file5 As String = _courseFiles.handoutFile5
            Dim _file6 As String = _courseFiles.handoutFile6
            Dim _file7 As String = _courseFiles.handoutFile7
            Dim _file8 As String = _courseFiles.handoutFile8
            For Each File As String In Request.Files
                _count += 1
                Dim hpf As HttpPostedFileBase = TryCast(Request.Files(File), HttpPostedFileBase)
                If hpf.ContentLength = 0 Then
                    Continue For
                End If

                Dim savedfileName As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + hpf.FileName
                hpf.SaveAs(savedfileName)
                _filename = hpf.FileName

                Select Case _count
                    Case Is = 1
                        If Not String.IsNullOrWhiteSpace(_file1) Then
                            If Not String.Compare(_eCourse.handoutFile1, _file1) = 0 AndAlso Not String.IsNullOrWhiteSpace(_eCourse.handoutFile1) Then
                                Dim FileToDelete As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + _file1
                                If System.IO.File.Exists(FileToDelete) = True Then
                                    System.IO.File.Delete(FileToDelete)
                                End If
                            End If
                        End If
                        _eCourse.handoutFile1 = _filename

                    Case Is = 2
                        If Not String.IsNullOrWhiteSpace(_file2) Then
                            If Not String.Compare(_eCourse.handoutFile2, _file2) = 0 AndAlso Not String.IsNullOrWhiteSpace(_eCourse.handoutFile2) Then
                                Dim FileToDelete As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + _file2
                                If System.IO.File.Exists(FileToDelete) = True Then
                                    System.IO.File.Delete(FileToDelete)
                                End If
                            End If
                        End If
                        _eCourse.handoutFile2 = _filename

                    Case Is = 3
                        If Not String.IsNullOrWhiteSpace(_file3) Then
                            If Not String.Compare(_eCourse.handoutFile3, _file3) = 0 AndAlso Not String.IsNullOrWhiteSpace(_eCourse.handoutFile3) Then
                                Dim FileToDelete As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + _file3
                                If System.IO.File.Exists(FileToDelete) = True Then
                                    System.IO.File.Delete(FileToDelete)
                                End If
                            End If
                        End If
                        _eCourse.handoutFile3 = _filename

                    Case Is = 4
                        If Not String.IsNullOrWhiteSpace(_file4) Then
                            If Not String.Compare(_eCourse.handoutFile4, _file4) = 0 AndAlso Not String.IsNullOrWhiteSpace(_eCourse.handoutFile4) Then
                                Dim FileToDelete As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + _file4
                                If System.IO.File.Exists(FileToDelete) = True Then
                                    System.IO.File.Delete(FileToDelete)
                                End If
                            End If
                        End If
                        _eCourse.handoutFile4 = _filename

                    Case Is = 5
                        If Not String.IsNullOrWhiteSpace(_file5) Then
                            If Not String.Compare(_eCourse.handoutFile5, _file5) = 0 AndAlso Not String.IsNullOrWhiteSpace(_eCourse.handoutFile5) Then
                                Dim FileToDelete As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + _file5
                                If System.IO.File.Exists(FileToDelete) = True Then
                                    System.IO.File.Delete(FileToDelete)
                                End If
                            End If
                        End If
                        _eCourse.handoutFile5 = _filename

                    Case Is = 6
                        If Not String.IsNullOrWhiteSpace(_file6) Then
                            If Not String.Compare(_eCourse.handoutFile6, _file6) = 0 AndAlso Not String.IsNullOrWhiteSpace(_eCourse.handoutFile6) Then
                                Dim FileToDelete As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + _file6
                                If System.IO.File.Exists(FileToDelete) = True Then
                                    System.IO.File.Delete(FileToDelete)
                                End If
                            End If
                        End If
                        _eCourse.handoutFile6 = _filename

                    Case Is = 7
                        If Not String.IsNullOrWhiteSpace(_file7) Then
                            If Not String.Compare(_eCourse.handoutFile7, _file7) = 0 AndAlso Not String.IsNullOrWhiteSpace(_eCourse.handoutFile7) Then
                                Dim FileToDelete As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + _file7
                                If System.IO.File.Exists(FileToDelete) = True Then
                                    System.IO.File.Delete(FileToDelete)
                                End If
                            End If
                        End If
                        _eCourse.handoutFile7 = _filename

                    Case Is = 8
                        If Not String.IsNullOrWhiteSpace(_file8) Then
                            If Not String.Compare(_eCourse.handoutFile8, _file8) = 0 AndAlso Not String.IsNullOrWhiteSpace(_eCourse.handoutFile8) Then
                                Dim FileToDelete As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory) + "\CourseHandouts\" + _file8
                                If System.IO.File.Exists(FileToDelete) = True Then
                                    System.IO.File.Delete(FileToDelete)
                                End If
                            End If
                        End If
                        _eCourse.handoutFile8 = _filename

                End Select

            Next

            UpdateModel(_eCourse)
            db.SaveChanges()


            Return RedirectToAction("CourseIndex")

      End Function

关于为什么会出错的任何想法?????

1 个答案:

答案 0 :(得分:1)

您没有将_eCourse附加到您的上下文中,因此不会更新它。 UpdateModel我认为这里根本不需要,因为它只是将您发布的表单值分配给您已经拥有的模型,因为eCourse是一个参数。做点什么(在电话上对不起) DB.Entry(_eCourse).State = EntityState.Modified

然后保存更改