' ---------------------------------------------------------
' Satya Kanithi's Editable Nested DataGrid
' ---------------------------------------------------------
'=======================================================
' FileName : WebForm1.aspx
' Description : Multi Purpose DataGrid, Which can be expandable to many child grids
' Date of Creation : Oct11, 2006
' Author : Satya Kanithi
'=======================================================
Imports System.Data.OleDb
Public Class WebForm1
Inherits System.Web.UI.Page
'--------------Control Declaration ----------
Protected WithEvents DataGrid1 As System.Web.UI.WebControls.DataGrid
Protected WithEvents DataGrid2 As System.Web.UI.WebControls.DataGrid
Protected WithEvents lblMessage As System.Web.UI.WebControls.Label
Protected WithEvents Literal1 As System.Web.UI.WebControls.Literal
#Region " Web Form Designer Generated Code "
'This call is required by the Web Form Designer.
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
End Sub
'NOTE: The following placeholder declaration is required by the Web Form Designer.
'Do not delete or move it.
Private designerPlaceholderDeclaration As System.Object
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: This method call is required by the Web Form Designer
'Do not modify it using the code editor.
InitializeComponent()
End Sub
#End Region
#Region "Variables"
Dim dgUniqueID As String
Dim dgEditItemIndex As Int32
Dim dgCurrentPageIndex As Int32
Dim dgSortExpression As String
Private Enum ExceptionType
Red = 1
Green = 2
Yellow = 3
End Enum
#End Region
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'//Clear the Message if any
lblMessage.Text = ""
If Not Page.IsPostBack Then
BindData()
'Reset the session variables
Session("CustomerID") = ""
Session("PrevItemIndex") = -1
dgSortExpression = ""
End If
End Sub
'//This procedure binds the DataGrid with Query Details
Private Sub BindData(Optional ByVal astrSort As String = "", Optional ByVal astrSort1 As String = "")
Dim lstrSQL As String
Dim ldtbParentTable As New DataTable
Dim ldtbChildTable As New DataTable
Dim ds As New DataSet
Dim lobjDataRelation As DataRelation
Dim lintPageSize As Int32
Dim llngTotalRec As Int32
Dim conn
Dim dcCust
Dim daCust
Dim dcOrder
Dim daOrder
Try
'//Prepare the connection object
conn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath(ConfigurationSettings.AppSettings("MDBPATH")))
conn.open()
'Query to get Customer Details - Parent Query
lstrSQL = "SELECT [Customers].[CustomerID], [Customers].[CompanyName], " & _
"[Customers].[ContactName],[Customers].[ContactTitle], " & _
"[Customers].[Address] FROM [Customers] "
'//Sort order provided
If astrSort <> "" Then
lstrSQL = lstrSQL & " ORDER BY " & astrSort
Else
'Default sort order
lstrSQL = lstrSQL & " ORDER BY [CUSTOMERS].[CUSTOMERID] ASC"
End If
dcCust = New OleDbCommand(lstrSQL, conn)
daCust = New OleDbDataAdapter(dcCust)
daCust.Fill(ldtbParentTable)
ldtbParentTable.TableName = "ParentTable"
'Query to get Order Details - Child Query
lstrSQL = "SELECT [Orders].[CustomerID] as ChildCustomerID,[Orders].[OrderID],[Orders].[ShipAddress]," & _
"[Orders].[Freight],[Orders].[ShipName] FROM [Orders]"
'//Sort order provided
If astrSort1 <> "" Then
lstrSQL = lstrSQL & " ORDER BY " & astrSort1
Else
'Default sort order
lstrSQL = lstrSQL & " ORDER BY [Orders].[OrderID] ASC"
End If
dcOrder = New OleDbCommand(lstrSQL, conn)
daOrder = New OleDbDataAdapter(dcOrder)
daOrder.Fill(ldtbChildTable)
ldtbChildTable.TableName = "ChildTable"
'Add both these tables to the dataset
ds.Tables.Add(ldtbParentTable)
ds.Tables.Add(ldtbChildTable)
'//Create relation and this relation name should be used on CreateChildView
Dim dr As New DataRelation("ParentTable_ChildTable", ldtbParentTable.Columns("CustomerID"), ldtbChildTable.Columns("ChildCustomerID"), False)
dr.Nested = True
ds.Relations.Add(dr)
'Set the datasource to parent datagrid
DataGrid1.DataSource = ds
DataGrid1.DataBind()
Catch exc As Exception
LogMessage(exc)
Exit Sub
Finally
daCust.Dispose()
dcCust.Dispose()
daOrder.Dispose()
dcOrder.Dispose()
ds.Dispose()
conn.close()
End Try
End Sub
'//Log messages
Sub LogMessage(ByVal exc As Exception, Optional ByVal param As Int32 = ExceptionType.Red)
If param = ExceptionType.Red Then
lblMessage.Text = exc.Message.ToString().Substring(0, exc.Message.Length - 1)
lblMessage.ForeColor = System.Drawing.Color.Red
ElseIf param = ExceptionType.Green Then
lblMessage.Text = exc.Message
lblMessage.ForeColor = System.Drawing.Color.Green
ElseIf param = ExceptionType.Yellow Then
lblMessage.Text = exc.Message
lblMessage.ForeColor = System.Drawing.Color.Yellow
End If
End Sub
#Region "DataGrid1 Event handlers"
'//This procedure handles the Parent Grid command events
Private Sub DataGrid1_ItemCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs) Handles DataGrid1.ItemCommand
Dim strSQL As String
Select Case e.CommandName
Case "Expand" '//Case for expanding the + sign on Parent grid to show the child grid
Dim img As ImageButton
Dim exp As PlaceHolder
'Before expanding, collapse previously opened child grid
Dim dgItem As DataGridItem
For Each dgItem In DataGrid1.Items
If dgItem.ItemIndex = Session("PrevItemIndex") And dgItem.ItemIndex <> e.Item.ItemIndex Then
img = dgItem.Cells(0).FindControl("ImageButton1")
If img.ImageUrl = "~/Images/Minus.gif" Then
img.ImageUrl = "~/Images/Plus.gif"
exp = dgItem.Cells(2).FindControl("Expanded")
exp.Visible = Not exp.Visible
End If
Exit For
End If
Next
img = e.Item.Cells(0).FindControl("ImageButton1")
If img.ImageUrl = "~/Images/Plus.gif" Then
img.ImageUrl = "~/Images/Minus.gif"
Else
img.ImageUrl = "~/Images/Plus.gif"
End If
exp = e.Item.Cells(2).FindControl("Expanded")
exp.Visible = Not exp.Visible
Session("PrevItemIndex") = e.Item.ItemIndex 'Store the ItemIndex in session variable
Session("CustomerID") = e.Item.Cells(1).Text 'Store the CustomerID
Case "Insert" '//Case statement for Insert Click on Parent Grid
Dim txtCustomerID As TextBox
Dim txtCompanyName As TextBox
Dim txtContactName As TextBox
Dim txtContactTitle As TextBox
Dim txtAddress As TextBox
Dim lstrCustomerID As String
Dim lstrCompanyName As String
Dim lstrContactName As String
Dim lstrContactTitle As String
Dim lstrRFC As String
Dim lstrAddress As String
'Read in the values of the TextBoxes
txtCustomerID = e.Item.FindControl("add_CustomerID")
lstrCustomerID = txtCustomerID.Text.ToUpper
txtCompanyName = e.Item.FindControl("add_CompanyName")
lstrCompanyName = txtCompanyName.Text
txtContactName = e.Item.FindControl("add_ContactName")
lstrContactName = txtContactName.Text
txtContactTitle = e.Item.FindControl("add_ContactTitle")
lstrContactTitle = txtContactTitle.Text
txtAddress = e.Item.FindControl("add_Address")
lstrAddress = txtAddress.Text
Dim conn
Dim dcCust
Try
'Check whether the record exists before adding...
strSQL = "SELECT COUNT(*) FROM [Customers] WHERE [Customers].[CustomerID] = '" & lstrCustomerID & "'"
conn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath(ConfigurationSettings.AppSettings("MDBPATH")))
dcCust = New OleDbCommand(strSQL, conn)
conn.Open()
Dim count = dcCust.ExecuteScalar
If (count > 0) Then
Throw New Exception("Record already exists...")
End If
dcCust.Dispose()
'Create the SQL statement for addition
strSQL = "INSERT INTO Customers (CustomerID, CompanyName, ContactName, " & _
"ContactTitle, Address) VALUES ('" & lstrCustomerID & "','" & lstrCompanyName & "','" & _
lstrContactName & "','" & lstrContactTitle & "','" & lstrAddress & "')"
dcCust = New OleDbCommand(strSQL, conn)
dcCust.ExecuteNonQuery()
LogMessage(New Exception("Record added successfully..."), ExceptionType.Green)
Catch exc As Exception
LogMessage(exc)
Exit Sub
Finally
dcCust.Dispose()
conn.Close()
End Try
'Rebind the DataGrid
BindData()
Case "Edit" '//Edit Case
DataGrid1.ShowFooter = False 'Hide the footer while editing
DataGrid1.EditItemIndex = e.Item.ItemIndex
BindData()
Case "Cancel" '//Cancel Case
Try
DataGrid1.ShowFooter = True
DataGrid1.EditItemIndex = -1
BindData()
Catch exc As Exception
LogMessage(exc)
Exit Sub
End Try
Case "Delete" '//Delete Case
Dim lstrCustomerID As String
Dim conn
Dim dcCust
'//Get the Customer ID which is hidden bound column
lstrCustomerID = e.Item.Cells(1).Text.ToUpper
Try
'Check whether the records exists in child table before deleting...
strSQL = "SELECT COUNT(*) FROM [Orders] WHERE [Orders].[CustomerID] = '" & lstrCustomerID & "'"
conn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath(ConfigurationSettings.AppSettings("MDBPATH")))
dcCust = New OleDbCommand(strSQL, conn)
conn.Open()
Dim count = dcCust.ExecuteScalar
If (count > 0) Then
Throw New Exception("Child records exists...")
End If
dcCust.Dispose()
'Create the SQL statement for addition
strSQL = "DELETE FROM Customers WHERE CustomerID = '" & lstrCustomerID & "'"
dcCust = New OleDbCommand(strSQL, conn)
dcCust.ExecuteNonQuery()
LogMessage(New Exception("Record deleted successfully..."), ExceptionType.Green)
Catch exc As Exception
LogMessage(exc)
Exit Sub
Finally
dcCust.Dispose()
conn.Close()
End Try
'Rebind the DataGrid
BindData()
Case "Update" '//Update Case
Dim txtCustomerID As TextBox
Dim txtCompanyName As TextBox
Dim txtContactName As TextBox
Dim txtContactTitle As TextBox
Dim txtAddress As TextBox
Dim lstrCustomerID As String
Dim lstrCompanyName As String
Dim lstrContactName As String
Dim lstrContactTitle As String
Dim lstrRFC As String
Dim lstrAddress As String
'Read in the values of the TextBoxes
txtCustomerID = e.Item.FindControl("edit_CustomerID") '//Customer ID will be in readonly format
lstrCustomerID = txtCustomerID.Text.ToUpper
txtCompanyName = e.Item.FindControl("edit_CompanyName")
lstrCompanyName = txtCompanyName.Text
txtContactName = e.Item.FindControl("edit_ContactName")
lstrContactName = txtContactName.Text
txtContactTitle = e.Item.FindControl("edit_ContactTitle")
lstrContactTitle = txtContactTitle.Text
txtAddress = e.Item.FindControl("edit_Address")
lstrAddress = txtAddress.Text
Dim conn
Dim dcCust
Try
'Create the SQL statement for updation
strSQL = "UPDATE Customers set CompanyName = '" & lstrCompanyName & "'"
strSQL = strSQL & ",ContactName = '" & lstrContactName & "'"
strSQL = strSQL & ",ContactTitle = '" & lstrContactTitle & "'"
strSQL = strSQL & ",Address = '" & lstrAddress & "'"
strSQL = strSQL & " WHERE CustomerID = '" & lstrCustomerID & "'"
conn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath(ConfigurationSettings.AppSettings("MDBPATH")))
dcCust = New OleDbCommand(strSQL, conn)
conn.Open()
dcCust.ExecuteNonQuery()
LogMessage(New Exception("Record updated successfully..."), ExceptionType.Green)
Catch exc As Exception
LogMessage(exc)
Exit Sub
Finally
dcCust.Dispose()
conn.Close()
End Try
'Rebind the DataGrid
DataGrid1.EditItemIndex = -1
BindData()
End Select
End Sub
'//This procedure is used for the purpose of edit on child grid
'//When your program uses the DataGrid control,
'//and your program has a child DataGrid control that is associated with each row of a parent DataGrid control,
'//a problem may occur. When you click Edit for the child DataGrid control, nothing happens.
'//This is known Microsoft Problem, I have used the resolution provided by Microsoft here
'//Refer http://support.microsoft.com/default.aspx?scid=kb;en-us;815004 for more details
Private Sub DataGrid1_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) Handles DataGrid1.ItemDataBound
Dim dgTemp As New DataGrid
If (e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem) Then
dgTemp = CType(e.Item.FindControl("DataGrid2"), DataGrid)
If dgTemp.UniqueID = dgUniqueID Then
dgTemp.EditItemIndex = dgEditItemIndex
'If the Edit Item Index is -1, On Cancel click
If (dgEditItemIndex = -1) Then
dgTemp.ShowFooter = True
Else
dgTemp.ShowFooter = False
End If
'Set the Page Index for child datagrid
dgTemp.CurrentPageIndex = dgCurrentPageIndex
'//Call the procedure to alter the Current Sort Expression
alterSortExpression(dgTemp)
'//Following code is for displaying back child grid after handling its button events
Dim img As ImageButton
img = e.Item.Cells(0).FindControl("ImageButton1")
img.ImageUrl = "~/Images/Minus.gif"
Dim exp As PlaceHolder
exp = e.Item.Cells(2).FindControl("Expanded")
exp.Visible = True
dgTemp.DataBind()
dgUniqueID = ""
dgEditItemIndex = -1
End If
End If
End Sub
'//Procedure for Parent DataGrid paging
Private Sub DataGrid1_PageIndexChanged(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridPageChangedEventArgs) Handles DataGrid1.PageIndexChanged
DataGrid1.CurrentPageIndex = e.NewPageIndex
BindData()
End Sub
'//Procedure for Parent DataGrid Sorting
Private Sub DataGrid1_SortCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridSortCommandEventArgs) Handles DataGrid1.SortCommand
Dim SortExprs() As String
Dim CurrentSearchMode As String, NewSearchMode As String
Dim ColumnToSort As String, NewSortExpr As String
' Parse the sort expression - delimiter space
SortExprs = Split(e.SortExpression, " ")
ColumnToSort = SortExprs(0)
' If a sort order is specified get it, else default is Ascending
If SortExprs.Length() > 1 Then
CurrentSearchMode = SortExprs(1).ToUpper()
If CurrentSearchMode = "ASC" Then
NewSearchMode = "DESC"
Else
NewSearchMode = "ASC"
End If
Else ' If no mode specified, Default is descending
NewSearchMode = "DESC"
End If
' Derive the new sort expression.
NewSortExpr = ColumnToSort & " " & NewSearchMode
' Figure out the column index
Dim iIndex As Integer
Select Case ColumnToSort.ToUpper()
Case "[CUSTOMERS].[CUSTOMERID]"
iIndex = 2
Case "[CUSTOMERS].[COMPANYNAME]"
iIndex = 3
Case "[CUSTOMERS].[CONTACTNAME]"
iIndex = 4
End Select
' alter the column's sort expression
DataGrid1.Columns(iIndex).SortExpression = NewSortExpr
'Reset the Page Number to start
DataGrid1.CurrentPageIndex = 0
' Sort the data in new order
BindData(NewSortExpr)
End Sub
#End Region
#Region "DataGrid2 Event handlers"
'//This procedure handles the Child Grid command events
'//On runtime child grid will have different UniqueID, E.G DataGrid_Ctl1, So we must use source object for DataGrid specific events
Public Sub DataGrid2_ItemCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs)
Dim strSQL As String
Select Case e.CommandName
Case "Insert"
Dim txtFreight As TextBox
Dim txtShipName As TextBox
Dim txtShipAddress As TextBox
Dim lstrCustomerID As String
Dim ldblFreight As Double
Dim lstrShipName As String
Dim lstrShipAddress As String
'//Here the Session variable being used was stored when the Parenrt grid '+' clicked
lstrCustomerID = Session("CustomerID")
'Read in the values of the TextBoxes
txtFreight = e.Item.FindControl("add_Freight")
ldblFreight = CDbl(txtFreight.Text)
txtShipName = e.Item.FindControl("add_ShipName")
lstrShipName = txtShipName.Text
txtShipAddress = e.Item.FindControl("add_ShipAddress")
lstrShipAddress = txtShipAddress.Text
Dim conn
Dim dcOrder
Try
conn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath(ConfigurationSettings.AppSettings("MDBPATH")))
'Create the SQL statement for addition
strSQL = "INSERT INTO Orders (CustomerID, Freight, ShipName, " & _
"ShipAddress) VALUES ('" & lstrCustomerID & "'," & ldblFreight & ",'" & _
lstrShipName & "','" & lstrShipAddress & "')"
dcOrder = New OleDbCommand(strSQL, conn)
conn.Open()
dcOrder.ExecuteNonQuery()
LogMessage(New Exception("Record added successfully..."), ExceptionType.Green)
Dim dgTemp As New DataGrid
dgTemp = CType(source, DataGrid)
dgUniqueID = dgTemp.UniqueID
dgEditItemIndex = -1
'//Set the current PageIndex
dgCurrentPageIndex = 0
Catch exc As Exception
LogMessage(exc)
Exit Sub
Finally
dcOrder.Dispose()
conn.Close()
End Try
'Rebind the DataGrid
BindData()
Case "Edit"
Try
'Cast dgTemp to incoming DataGrid
Dim dgTemp As New DataGrid
dgTemp = CType(source, DataGrid)
'//Getting the UniqueID of the child datagrid using the source object
dgUniqueID = dgTemp.UniqueID
'//Store the EditItemIndex to be used later in DataGrid1_ItemDataBound procedure
dgEditItemIndex = e.Item.ItemIndex
'//Store the current PageIndex
dgCurrentPageIndex = dgTemp.CurrentPageIndex
BindData()
Catch exc As Exception
LogMessage(exc)
Exit Sub
End Try
Case "Cancel"
Try
'Cast dgTemp to incoming DataGrid
Dim dgTemp As New DataGrid
dgTemp = CType(source, DataGrid)
dgUniqueID = dgTemp.UniqueID
dgEditItemIndex = -1
'//Store the current PageIndex
dgCurrentPageIndex = dgTemp.CurrentPageIndex
BindData()
Catch exc As Exception
LogMessage(exc)
Exit Sub
End Try
Case "Update"
Dim txtOrderID As TextBox
Dim txtFreight As TextBox
Dim txtShipName As TextBox
Dim txtShipAddress As TextBox
Dim ldblFreight As Double
Dim lstrShipName As String
Dim lstrShipAddress As String
Dim lintOrderID As Int64
'Read in the values of the TextBoxes
txtOrderID = e.Item.FindControl("edit_OrderID")
lintOrderID = CInt(txtOrderID.Text) '//Order ID will be in Readonly format
txtFreight = e.Item.FindControl("edit_Freight")
ldblFreight = CDbl(txtFreight.Text)
txtShipName = e.Item.FindControl("edit_ShipName")
lstrShipName = txtShipName.Text
txtShipAddress = e.Item.FindControl("edit_ShipAddress")
lstrShipAddress = txtShipAddress.Text
Dim conn
Dim dcOrder
Try
conn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath(ConfigurationSettings.AppSettings("MDBPATH")))
'Create the SQL statement for updation
strSQL = "UPDATE Orders set Freight = " & ldblFreight
strSQL = strSQL & ",ShipName = '" & lstrShipName & "'"
strSQL = strSQL & ",ShipAddress = '" & lstrShipAddress & "'"
strSQL = strSQL & " WHERE OrderID = " & lintOrderID
dcOrder = New OleDbCommand(strSQL, conn)
conn.Open()
dcOrder.ExecuteNonQuery()
LogMessage(New Exception("Record updated successfully..."), ExceptionType.Green)
'Cast dgTemp to incoming DataGrid
Dim dgTemp As New DataGrid
dgTemp = CType(source, DataGrid)
dgUniqueID = dgTemp.UniqueID
dgEditItemIndex = -1
'//Store the current PageIndex
dgCurrentPageIndex = dgTemp.CurrentPageIndex
Catch exc As Exception
LogMessage(exc)
Exit Sub
Finally
dcOrder.Dispose()
conn.Close()
End Try
'Rebind the DataGrid
BindData()
Case "Delete"
Dim ldblOrderID As Int64
'Read in the BoundColumn value of the hidden Order ID value
ldblOrderID = CInt(e.Item.Cells(0).Text)
Dim conn
Dim dcOrder
Try
conn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath(ConfigurationSettings.AppSettings("MDBPATH")))
'Create the SQL statement for addition
strSQL = "DELETE FROM Orders WHERE OrderID = " & ldblOrderID
dcOrder = New OleDbCommand(strSQL, conn)
conn.Open()
dcOrder.ExecuteNonQuery()
LogMessage(New Exception("Record deleted successfully..."), ExceptionType.Green)
'Cast dgTemp to incoming DataGrid
Dim dgTemp As New DataGrid
dgTemp = CType(source, DataGrid)
dgUniqueID = dgTemp.UniqueID
dgEditItemIndex = -1
'//Set the current PageIndex
dgCurrentPageIndex = 0
Catch exc As Exception
LogMessage(exc)
Exit Sub
Finally
dcOrder.Dispose()
conn.Close()
End Try
'Rebind the DataGrid
BindData()
End Select
End Sub
'//Procedure for Child DataGrid paging
Public Sub DataGrid2_PageIndexChanged(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridPageChangedEventArgs)
dgCurrentPageIndex = e.NewPageIndex
'Cast dgTemp to incoming DataGrid
Dim dgTemp As New DataGrid
dgTemp = CType(source, DataGrid)
'//Getting the UniqueID of the child datagrid using the source object
dgUniqueID = dgTemp.UniqueID
'//Store the EditItemIndex to be used later in DataGrid1_ItemDataBound procedure
dgEditItemIndex = -1
BindData()
End Sub
'//Procedure for Child DataGrid Sorting
Public Sub DataGrid2_SortCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridSortCommandEventArgs)
'//Store the Sort expression, to be used later
dgSortExpression = e.SortExpression
'Cast dgTemp to incoming DataGrid
Dim dgTemp As New DataGrid
dgTemp = CType(source, DataGrid)
'//Getting the UniqueID of the child datagrid using the source object
dgUniqueID = dgTemp.UniqueID
'//Store the EditItemIndex to be used later in DataGrid1_ItemDataBound procedure
dgEditItemIndex = -1
dgCurrentPageIndex = 0
'//Get the Sort Expression to sort the child grid
Dim SortExpr As String
SortExpr = getSortExpression(dgTemp)
BindData(, SortExpr)
End Sub
'//This function returns the new sort expression to sort the child DataGrid
Private Function getSortExpression(ByVal dgTemp As DataGrid) As String
Dim SortExprs() As String
Dim CurrentSearchMode As String, NewSearchMode As String
Dim ColumnToSort As String, NewSortExpr As String
' Parse the sort expression - delimiter space
SortExprs = Split(dgSortExpression, " ")
ColumnToSort = SortExprs(0)
' If a sort order is specified get it, else default is Ascending
If SortExprs.Length() > 1 Then
CurrentSearchMode = SortExprs(1).ToUpper()
If CurrentSearchMode = "ASC" Then
NewSearchMode = "DESC"
Else
NewSearchMode = "ASC"
End If
Else ' If no mode specified, Default is descending
NewSearchMode = "DESC"
End If
' Derive the new sort expression.
NewSortExpr = ColumnToSort & " " & NewSearchMode
Return NewSortExpr
End Function
'//This function alters the child datagrid sort expression
Private Sub alterSortExpression(ByVal dgTemp As DataGrid)
Dim SortExprs() As String
Dim ColumnToSort As String, NewSortExpr As String
' Parse the sort expression - delimiter space
SortExprs = Split(dgSortExpression, " ")
ColumnToSort = SortExprs(0)
' Figure out the column index
Dim iIndex As Integer
Select Case ColumnToSort.ToUpper()
Case "[ORDERS].[ORDERID]"
iIndex = 1
Case "[ORDERS].[FREIGHT]"
iIndex = 2
Case "[ORDERS].[SHIPNAME]"
iIndex = 3
End Select
' alter the column's sort expression
dgTemp.Columns(iIndex).SortExpression = getSortExpression(dgTemp)
End Sub
#End Region
End Class
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