Question

在较旧的WinForms应用程序中，这有效，但在WPF中，它只会移动项目一次，唯一的当前解决方法是将其保存到后端数据库，再次打开并再移动一个空间。列表项由DataTable提供

Private Sub Reports_BalanceSheet_ListBoxMoveUp(LB As ListBox, DT As DataTable, DisplayName As String, Optional MasterListBox As ListBox = Nothing)
    Try
        Dim StartIndex As Integer = LB.SelectedIndex
        Dim CatID As Integer = 0

        'Update the datasource
        Dim SR() As DataRow
        If DisplayName = "Name" Then
            SR = DT.Select("ID > 0 AND FormID = " & Form_ID, Nothing)
        Else
            CatID = MasterListBox.SelectedValue
            'Check that the positions are correct
            If DataChanged = False Then
                Dim vRowID As Integer = 0
                For Each Row As DataRow In DT.Rows
                    If Row("FormID") = Form_ID And Row("CatID") = CatID Then
                        Row("Position") = vRowID
                        vRowID += 1
                    End If
                Next
            End If

            SR = DT.Select("ID > 0 AND FormID = " & Form_ID & " AND CatID = " & CatID, "Position")
        End If
        Dim vString As String = ""
        Dim vUpperID As Integer = 0
        Dim vCurrentID As Integer = 0
        For Each Row As DataRow In SR
            Dim vPos As Integer = Row("Position")
            If vPos = StartIndex - 1 Then
                vUpperID = Row("ID")
            End If
            If vPos = StartIndex Then
                vCurrentID = Row("ID")
            End If
        Next
        If Not vUpperID = 0 And Not vCurrentID = 0 Then
            DT.Select("ID = " & vUpperID)(0)("Position") = StartIndex
            DT.Select("ID = " & vCurrentID)(0)("Position") = StartIndex - 1
            If DisplayName = "Name" Then
                DT.DefaultView.RowFilter = "FormID = " & Form_ID
            Else
                DT.DefaultView.RowFilter = "FormID = " & Form_ID & " AND CatID = " & CatID
            End If

            DT.DefaultView.Sort = "Position"
            DT = DT.DefaultView.ToTable
            DT.AcceptChanges()

            With LB
                .SelectedValuePath = "ID"
                .DisplayMemberPath = DisplayName
                .ItemsSource = DT.DefaultView
                .SelectedValue = vCurrentID
                .UpdateLayout()
            End With
        End If


    Catch ex As Exception
        EmailError(ex)
    End Try
End Sub

Answer 1

以这种方式工作（并且代码更少）： - ）

 Dim StartIndex As Integer = LB.SelectedIndex
        Dim vTotalRows As Integer = DT.Rows.Count - 1
        If Not StartIndex = vTotalRows Then
            Dim vSelected As DataRow = DT.Rows(StartIndex)
            Dim vNew As DataRow = DT.NewRow()
            vNew.ItemArray = vSelected.ItemArray
            DT.Rows.Remove(vSelected)
            DT.Rows.InsertAt(vNew, StartIndex + 1)

            LB.SelectedIndex = StartIndex + 1

            Dim vPos As Integer = 0
            For Each Row As DataRow In DT.Rows
                Row("Position") = vPos
                vPos += 1
            Next
        End If

WPF ListBox - 上下移动项目

1 个答案: