Come ordinare una GridView in ASP NET
Riporto qui il codice in Visual Basic NET per riordinare il controllo gridview in ASP NET.
Inserire un pulsante e fare riferimento a questa SUB che andrà a popolare una gridview e un datatable:
Protected dv As DataView
Private Sub loadGvElenco()
Dim Classe as new Classe()
Try
Dim ds As DataSet
ds = getDSSearch(Classe)
dv = ds.Tables(0).DefaultView
gvElenco.DataSource = dv
dv.Sort = hidOrdinamento.Value
gvElenco.DataBind()
Catch ex As Exception
Throw ex
End Try
End Sub
dove getDSSearch popola tramite un DB il Dataset DS. Poi inserire questo codice.
#Region "Ordinamento del GridView"
Sub GridViewSortImages(ByRef sender As Object, ByRef e As GridViewRowEventArgs)
Dim senderGridView As GridView = CType(sender, GridView)
Dim space As New Literal
space.Text = " "
If Not (e.Row Is Nothing) AndAlso e.Row.RowType = DataControlRowType.Header Then
For Each cell As TableCell In e.Row.Cells
If cell.HasControls Then
Dim button As LinkButton = CType((cell.Controls(0)), LinkButton)
If Not (button Is Nothing) Then
If GridViewSortExpression = button.CommandArgument Then
If GridViewSortDirection = "ASC" Then
button.Attributes("onmouseover") = "document.getElementById(’imgOrd" & cell.ClientID & "’).src=’../../images/sort_asc_h.gif’;"
button.Attributes("onmouseout") = "document.getElementById(’imgOrd" & cell.ClientID & "’).src=’../../images/sort_asc.gif’;"
button.Text = button.Text & "<img id=""imgOrd" & cell.ClientID & """ border=""0"" src=""../../images/sort_asc.gif"" />"
Else
button.Attributes("onmouseover") = "document.getElementById(’imgOrd" & cell.ClientID & "’).src=’../../images/sort_desc_h.gif’;"
button.Attributes("onmouseout") = "document.getElementById(’imgOrd" & cell.ClientID & "’).src=’../../images/sort_desc.gif’;"
button.Text = button.Text & "<img id=""imgOrd" & cell.ClientID & """ border=""0"" src=""../../images/sort_desc.gif"" />"
End If
Else
button.Attributes("onmouseover") = "document.getElementById(’imgOrd" & cell.ClientID & "’).src=’../../images/sort_none_h.gif’;"
button.Attributes("onmouseout") = "document.getElementById(’imgOrd" & cell.ClientID & "’).src=’../../images/sort_none.gif’;"
button.Text = button.Text & "<img id=""imgOrd" & cell.ClientID & """ border=""0"" src=""../../images/sort_none.gif"" />"
End If
End If
End If
Next
End If
End Sub
Private Property GridViewSortDirection() As String
Get
Return IIf(ViewState("SortDirection") = Nothing, "ASC", ViewState("SortDirection"))
End Get
Set(ByVal value As String)
ViewState("SortDirection") = value
End Set
End Property
Private Property GridViewSortExpression() As String
Get
Return IIf(ViewState("SortExpression") = Nothing, String.Empty, ViewState("SortExpression"))
End Get
Set(ByVal value As String)
ViewState("SortExpression") = value
End Set
End Property
Private Function GetSortDirection() As String
Select Case GridViewSortDirection
Case "ASC"
GridViewSortDirection = "DESC"
Case "DESC"
GridViewSortDirection = "ASC"
End Select
Return GridViewSortDirection
End Function
Protected Sub gvElenco_RowCreated(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles gvElenco.RowCreated
Try
GridViewSortImages(sender, e)
Catch ex As Exception
lblMessaggio.Text = ex.Message.ToString()
End Try
End Sub
Protected Sub gvElenco_Sorting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewSortEventArgs) Handles gvElenco.Sorting
Try
GridViewSortExpression = e.SortExpression
Dim pageIndex As Integer = gvElenco.PageIndex
SortDataTable(False)
Catch ex As Exception
lblMessaggio.Text = ex.Message.ToString()
End Try
End Sub
Protected Sub SortDataTable(ByVal isPageIndexChanging As Boolean)
Dim strSort As String = ""
Try
If GridViewSortExpression <> String.Empty Then
If isPageIndexChanging Then
strSort = String.Format("{0} {1}", GridViewSortExpression, GridViewSortDirection)
Else
strSort = String.Format("{0} {1}", GridViewSortExpression, GetSortDirection())
End If
hidOrdinamento.Value = strSort
loadGvElenco()
End If
Catch ex As Exception
lblMessaggio.Text = ex.Message.ToString()
End Try
End Sub
#End Region