editform.vb

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Imports System.Xml.Serialization
Imports System.IO

Public Class frmEdit

	Private blnIsLoaded As Boolean
    Private blnUseBindingSource As Boolean  '= True
    Private objNwind As Northwind
    Private Const strIEFile As String = "\Program Files\Internet Explorer\Iexplore.exe"
    Private strPath As String
    Private strFile As String
    Private alCustomers As New ArrayList
    Private alOrders As New ArrayList
    Private alOrder_Details As New ArrayList

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        If File.Exists("..\Output.xml") Then
            File.Delete("..\Output.xml")
        End If
    End Sub

    Private Sub btnLoadData_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLoadData.Click
        Dim lngTicks As Long = Now.Ticks
        Dim intRows As Integer
        txtTime.Text = ""
        blnIsLoaded = False
        Me.Cursor = Cursors.WaitCursor
        'Hydrate the NorthwindDS object by deserializing it
        objNwind = New Northwind
        Dim xsInput As New XmlSerializer(objNwind.GetType)
        Dim fsInput As New FileStream("..\Northwind.xml", FileMode.Open)
        objNwind = CType(xsInput.Deserialize(fsInput), Northwind)
        fsInput.Close()

        'ArrayLists work as DataSource, but no benefit
        'alCustomers = ArrayList.Adapter(objNwind.Customers)
        'alOrders = ArrayList.Adapter(objNwind.Orders)
        'alOrder_Details = ArrayList.Adapter(objNwind.Order_Details)

        If chkUseBindingSource.Checked Then
            With NorthwindCustomersBindingSource
                .Clear()
                Application.DoEvents()
                '.DataSource = alCustomers
                .DataSource = objNwind
                .DataMember = "Customers"
                With NorthwindCustomersDataGridView
                    .DataSource = NorthwindCustomersBindingSource
                    .DataMember = ""
                End With
                intRows += .Count
            End With
            Application.DoEvents()
            With NorthwindOrdersBindingSource
                .Clear()
                Application.DoEvents()
                '.DataSource = alOrders
                .DataSource = objNwind
                .DataMember = "Orders"
                'Unfortunately, not supported on arrays
                '.Sort = "OrderID DESC"
                '.Filter = "CustomerID = '" + Me.NorthwindCustomersBindingSource.Item(0).ToString + "'"
                With NorthwindOrdersDataGridView
                    .DataSource = NorthwindOrdersBindingSource
                    .DataMember = ""
                End With
                intRows += .Count
            End With
            Application.DoEvents()
            With NorthwindOrder_DetailsBindingSource
                .Clear()
                Application.DoEvents()
                '.DataSource = alOrder_Details
                .DataSource = objNwind
                .DataMember = "Order_Details"
                '.Sort = "ProductID"
                '.Filter = "OrderID = " + Me.NorthwindOrdersBindingSource.Item(0).ToString
                With NorthwindOrder_DetailsDataGridView
                    .DataSource = NorthwindOrder_DetailsBindingSource
                    .DataMember = ""
                End With
                intRows += .Count
            End With
        Else
            With NorthwindCustomersDataGridView
                .DataSource = objNwind
                .DataMember = "Customers"
                Application.DoEvents()
                intRows += .Rows.Count
            End With

            With NorthwindOrdersDataGridView
                .DataSource = objNwind
                .DataMember = "Orders"
                Application.DoEvents()
                intRows += .Rows.Count
            End With
            With NorthwindOrder_DetailsDataGridView
                .DataSource = objNwind
                .DataMember = "Order_Details"
                Application.DoEvents()
                intRows += .Rows.Count
            End With
        End If
        Me.Cursor = Cursors.Default
        blnIsLoaded = True
        lngTicks = Now.Ticks - lngTicks
        txtTime.Text = Format(lngTicks / 10000000, "0.00")
    End Sub

    Private Sub NorthwindCustomersBindingSource_CurrentChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles NorthwindCustomersBindingSource.CurrentChanged
        If blnIsLoaded And blnUseBindingSource Then
            With NorthwindCustomersBindingSource
                Dim strCustomerID As String = .Item(0).ToString
                With NorthwindOrdersDataGridView
                    Dim intRow As Integer
                    For intRow = 0 To .Rows.Count - 1
                        If .Rows(intRow).Cells(1).ToString = strCustomerID Then
                            .Rows(intRow).Visible = True
                        Else
                            .Rows(intRow).Visible = False
                        End If
                    Next
                    '.Sort(.Columns(0), System.ComponentModel.ListSortDirection.Descending)
                End With
            End With
        End If
    End Sub

    Private Sub NorthwindOrdersBindingSource_CurrentChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles NorthwindOrdersBindingSource.CurrentChanged
        If blnIsLoaded And blnUseBindingSource Then
            With NorthwindOrdersBindingSource
                Dim strOrderID As String = .Item(0).ToString
                With NorthwindOrder_DetailsDataGridView
                    Dim intRow As Integer
                    For intRow = 0 To .Rows.Count - 1
                        If .Rows(intRow).Cells(0).ToString = strOrderID Then
                            .Rows(intRow).Visible = True
                        Else
                            .Rows(intRow).Visible = False
                        End If
                    Next
                    '.Sort(.Columns(0), System.ComponentModel.ListSortDirection.Descending)
                End With
            End With
        End If
    End Sub

    Private Sub btnSaveData_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSaveData.Click
        'End the edits
        If chkUseBindingSource.Checked Then
            NorthwindCustomersBindingSource.EndEdit()
            NorthwindOrdersBindingSource.EndEdit()
            NorthwindOrder_DetailsBindingSource.EndEdit()
        Else
            NorthwindCustomersDataGridView.EndEdit(DataGridViewDataErrorContexts.Commit)
            NorthwindOrdersDataGridView.EndEdit(DataGridViewDataErrorContexts.Commit)
            NorthwindOrder_DetailsDataGridView.EndEdit(DataGridViewDataErrorContexts.Commit)
        End If

        'Dehydrate the Northwind object by serializing it to Output.xml
        Dim xsOutput As New XmlSerializer(objNwind.GetType)
        Dim srOutput As New StreamWriter("..\Output.xml")
        xsOutput.Serialize(srOutput, objNwind)
        srOutput.Close()
        If File.Exists(strIEFile) And File.Exists("..\Output.xml") Then
            strPath = Application.StartupPath
            strPath = Mid(strPath, 1, strPath.LastIndexOf("\"))
            strFile = strPath + "\Output.xml"
            Dim strShell As String = """" + strIEFile + """ " + strFile
            Shell(strShell, AppWinStyle.NormalFocus)
        End If
    End Sub

    Private Sub NorthwindCustomersDataGridView_RowEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles NorthwindCustomersDataGridView.RowEnter
        If blnIsLoaded And Not blnUseBindingSource Then
            Dim strCustomerID As String
            With NorthwindCustomersDataGridView
                strCustomerID = .Rows(e.RowIndex).Cells(0).Value.ToString
            End With
            With NorthwindOrdersDataGridView
                Dim intRow As Integer
                Dim alBands As New ArrayList
                Dim rowBand As DataGridViewBand
                For intRow = 0 To .Rows.Count - 1
                    rowBand = .Rows(intRow)
                    If .Rows(intRow).Cells(1).ToString = strCustomerID Then
                        rowBand.Visible = True
                        '.Rows(intRow).Visible = True
                    Else
                        alBands.Add(rowBand)
                        'rowBand.Visible = False
                        '.Rows(intRow).Visible = False
                    End If
                Next
                For intRow = 0 To alBands.Count - 1
                    rowBand = CType(alBands(intRow), DataGridViewBand)
                    'rowBand.Visible = False
                Next
            End With
        End If
    End Sub
End Class