Hello there!

 This example works fine to me, except for one case. I use the GridView together with the FormView. whenever OnSelectedIndexChanged is fired, the sorting and paging is messed up.

Does anyone have any ideas on how to keep the sorting and paging when this event is fired?
 

aspnet_spnt:

I want to sort a date column in a grid view and iam using the following code. Iam getting an error The server tag is not well formed.    

<asp:TemplateField HeaderText ="Date Injured">
          <EditItemTemplate>
          <asp:Label  ID="Label3" runat="server" Text=‘<%# Eval("DATE", "{0:MM/dd/yyyy}") %>‘></asp:Label>
          </EditItemTemplate>
          <Itemtemplate>
    <asp:Label ID="Label3" runat="server" Text=’<%# Bind(“DATE”, “{0:MM/dd/yyyy}”) %>‘> </asp:Label>
   </itemtemplate>
</asp:TemplateField>

What line is the exception referring to? 

Error 1 C:\Inetpub\wwwroot\accident\admin\Default.aspx: ASP.NET runtime error: A call to Bind must be assigned to a property of a control inside a template. C:\Inetpub\wwwroot\accident\admin\Default.aspx 88.   This error is occouring at line 88 which is   <asp:Label ID="Label3" runat="server" Text=’<%# Bind(“DATE”, “{0:MM/dd/yyyy}”) %>‘> </asp:Label>
and also its bringing up another error

 Error 2 The server tag is not well formed. C:\Inetpub\wwwroot\accident\admin\Default.aspx 85 . Line 85 is <asp:Label  ID="Label3" runat="server" Text=‘<%# Eval("DATE", "{0:MM/dd/yyyy}") %>‘></asp:Label>

We're binding our GridView to a list object we get back from our CodeGen class, this is how I got ours to work:

    public SortDirection GridViewSortDirection

    {

        get

        {

            if (ViewState["sortDirection"] == null)

                ViewState["sortDirection"] = SortDirection.Ascending;

            return (SortDirection)ViewState["sortDirection"];

        }

        set { ViewState["sortDirection"] = value; }

    }

    protected void gridView_Sorting(object sender, GridViewSortEventArgs e)

    {

        // Now switch the sortexpression

        string sortExpression = e.SortExpression;

        if (GridViewSortDirection == SortDirection.Ascending)

        {

            GridViewSortDirection = SortDirection.Descending;

        }

        else

        {

            GridViewSortDirection = SortDirection.Ascending;

        }

        List<sss.DataTier.Interact.Podcast> podcastList = gvPodcasts.DataSource as List<sss.DataTier.Interact.Podcast>;

        sss.DataTier.Interact.Podcast.Comparer podcastComparer = new PodcastBase.Comparer(PodcastBase.PodcastColumn.Title);

        podcastList.Sort(podcastComparer);

        if (e.SortDirection == GridViewSortDirection)

        {

            podcastList.Reverse();

        }

        gvPodcasts.DataSource = podcastList;

        gvPodcasts.DataBind();

    }

Hi All

 I've found this section of the forum really usefull. Its really got me out of a Jam. I can't help but think though that it'd be nicer if I could encapsulate this code into a Business object. I tried but I wasn't sure how I would be able to access the gridview? Would I need to use atrtributes to specify that I was returning some data?

 I'm going to keep at this, when I can anyway, so if anyone could help that'd be great.

 Liam

LiamHughes1981:

I've found this section of the forum really usefull. Its really got me out of a Jam. I can't help but think though that it'd be nicer if I could encapsulate this code into a Business object. I tried but I wasn't sure how I would be able to access the gridview? Would I need to use atrtributes to specify that I was returning some data?

I'm going to keep at this, when I can anyway, so if anyone could help that'd be great.

You should be able to put the sorting/paging code in a separate class. Give it a try and let me know if you have any problems.

Damn I was kind of hoping you do it for me! My first attempt didn't go well!

 I'll crack on and get back to you

Hello,

i'm trying to run your solution with code behind file but I get this error :

"System.InvalidCastException: Impossible d'effectuer un cast d'un objet de type 'System.Data.DataView' en type 'System.Data.DataTable'."

I don't understand why it doesn't work with codebehind file.

Here is my code :

default2.aspx :

<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default2.aspx.vb" Inherits="Default2" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Page sans titre</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:GridView ID="gridViewPublishers" runat="server" AllowPaging="true" AllowSorting="true"
            AutoGenerateColumns="false" EmptyDataText="No records found" OnPageIndexChanging="gridViewPublishers_PageIndexChanging"
            OnSorting="gridViewPublishers_Sorting" PagerSettings-Mode="NumericFirstLast"
            PageSize="25">
            <AlternatingRowStyle BackColor="LightGray" />
            <HeaderStyle BackColor="Gray" Font-Bold="true" Font-Names="Verdana" Font-Size="Small" />
            <PagerStyle BackColor="DarkGray" Font-Names="Verdana" Font-Size="Small" />
            <RowStyle Font-Names="Verdana" Font-Size="Small" />
            <Columns>
                <asp:BoundField DataField="PubID" HeaderText="Publisher ID" SortExpression="PubID" />
                <asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" />
                <asp:BoundField DataField="Company Name" HeaderText="Company Name" SortExpression="Company Name" />
                <asp:BoundField DataField="Address" HeaderText="Address" SortExpression="Address" />
                <asp:BoundField DataField="City" HeaderText="City" SortExpression="City" />
                <asp:BoundField DataField="State" HeaderText="State" SortExpression="State" />
                <asp:BoundField DataField="Zip" HeaderText="Zip" SortExpression="Zip" />
                <asp:BoundField DataField="Telephone" HeaderText="Telephone" SortExpression="Telephone" />
                <asp:BoundField DataField="Fax" HeaderText="Fax" SortExpression="Fax" />
                <asp:BoundField DataField="Comments" HeaderText="Comments" SortExpression="Comments" />
            </Columns>
        </asp:GridView>
    
    </div>
    </form>
</body>
</html>

Default2.aspx.vb

Imports System.Data
Imports System.Data.OleDb

Partial Class Default2
    Inherits System.Web.UI.Page

    Private Sub PopulatePublishersGridView()
        Dim connectionString As String = AccessConnectionString()
        Dim accessConnection As OleDbConnection = New OleDbConnection(connectionString)

        Dim sqlQuery As String = "SELECT [PubID], [Name], [Company Name], [Address], [City], [State], [Zip], [Telephone], [Fax], [Comments] FROM Publishers ORDER BY [Name] ASC;"

        Dim accessCommand As New OleDbCommand(sqlQuery, accessConnection)

        Dim publishersDataAdapter As New OleDbDataAdapter(accessCommand)
        Dim publishersDataTable As New DataTable("Publishers")
        publishersDataAdapter.Fill(publishersDataTable)

        Dim dataTableRowCount As Integer = publishersDataTable.Rows.Count

        If dataTableRowCount > 0 Then
            gridViewPublishers.DataSource = publishersDataTable
            gridViewPublishers.DataBind()
        End If
    End Sub

    Private Function AccessConnectionString() As String
        Dim accessDatabasePath As String = Server.MapPath("~/App_Data/biblio.mdb")
        Return String.Format("Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0};", accessDatabasePath)
    End Function

    Private Property GridViewSortDirection() As String
        Get
            Return IIf(ViewState("SortDirection") = Nothing, "DESC", ViewState("SortDirection"))
        End Get
        Set(ByVal value As String)
            ViewState("SortDirection") = value
        End Set
    End Property

    Private Property GridViewSortBLOCKED EXPRESSION 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 Function SortDataTable(ByVal dataTable As DataTable, ByVal isPageIndexChanging As Boolean) As DataView
        If Not dataTable Is Nothing Then
            Dim dataView As New DataView(dataTable)
            If GridViewSortExpression <> String.Empty Then
                If isPageIndexChanging Then
                    dataView.Sort = String.Format("{0} {1}", GridViewSortExpression, GridViewSortDirection)
                Else
                    dataView.Sort = String.Format("{0} {1}", GridViewSortExpression, GetSortDirection())
                End If
            End If
            Return dataView
        Else
            Return New DataView()
        End If
    End Function


    Protected Sub gridViewPublishers_PageIndexChanging(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewPageEventArgs) Handles gridViewPublishers.PageIndexChanging
        gridViewPublishers.DataSource = SortDataTable(gridViewPublishers.DataSource, True)
        gridViewPublishers.PageIndex = e.NewPageIndex
        gridViewPublishers.DataBind()
    End Sub

    Protected Sub gridViewPublishers_Sorting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewSortEventArgs) Handles gridViewPublishers.Sorting
        GridViewSortExpression = e.SortExpression
        Dim pageIndex As Integer = gridViewPublishers.PageIndex
        gridViewPublishers.DataSource = SortDataTable(gridViewPublishers.DataSource, False)
        gridViewPublishers.DataBind()
        gridViewPublishers.PageIndex = pageIndex
    End Sub

    Protected Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
        PopulatePublishersGridView()
    End Sub
End Class

thanks a lot

Coroebus:

i'm trying to run your solution with code behind file but I get this error :

"System.InvalidCastException: Impossible d'effectuer un cast d'un objet de type 'System.Data.DataView' en type 'System.Data.DataTable'."

I don't understand why it doesn't work with codebehind file.

Could you post what line it's referring to as well as the stack trace?

Hi

 I managed to get the code into a class. This is it:

public class GridViewHelper

}

Actually Scratch one of them issues. The paging is persisting where I use the code

Grid1.PageIndex = Grid1.PageIndex;

 But the I can't figure out a way to get the current sort column from the gridview. Any ideas?

I'm getting really stuck here now. The page index works because I'm altering the Gridview itself. So I can then still access the page index from the GridView. But because the sort script sorts the DataView of the GridView there is no information to access on what is sorted and in which direction. There fore as soon as I page the GridView the system rebinds the GridView and overwrites the sorted DataView.

I tried sorting the GridView directly using the code Grid1.Sort(...) but as soon as I called this fucntion it activated the OnSorting function, which contained this code and the program went into a loop.

 So I'm stuck! I need to find out what the sorting column and direction is but there is no way to access this informaction.

Here's my code again (why have a suddenly started writing in red??!)

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

/// <summary>
/// Summary description for GridViewHelper
/// </summary>
namespace ljmu.Helpers
{
    public class GridViewHelper
    {
	    public GridViewHelper()
	    {

	    }

        private string ConvertSortDirectionToSql(SortDirection sortDirection)
        {
            string newSortDirection = String.Empty;

            switch (sortDirection)
            {
                case SortDirection.Ascending:
                    newSortDirection = "ASC";
                    break;

                case SortDirection.Descending:
                    newSortDirection = "DESC";
                    break;
            }

            return newSortDirection;
        }

        public GridView GridViewPage(GridView Grid1, int Page)
        {
            SortDirection y = Grid1.SortDirection;
            string w = Grid1.SortExpression;
            Grid1.PageIndex = Page;
            return Grid1;
        }

        public GridView GridViewSort(DataTable dataTable, GridViewSortEventArgs e, GridView Grid1)
        {
            DataView dataView = new DataView(dataTable);
            dataView.Sort = e.SortExpression + " " + ConvertSortDirectionToSql(e.SortDirection);
            Grid1.DataSource = dataView;
            Grid1.PageIndex = Grid1.PageIndex;
            return Grid1;
        }
    }
}

StrongTypes:

Coroebus:

i'm trying to run your solution with code behind file but I get this error :

"System.InvalidCastException: Impossible d'effectuer un cast d'un objet de type 'System.Data.DataView' en type 'System.Data.DataTable'."

I don't understand why it doesn't work with codebehind file.

Could you post what line it's referring to as well as the stack trace?

line is :

gridViewPublishers.DataSource = SortDataTable(Me.gridViewPublishers.DataSource, False)

Ryan:

• I'm trying to adapt your code to VB.net 2005 using different architecture. The code is temporarily in the presentation class.

    Protected Sub gvSearch_Sorting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewSortEventArgs) Handles gvSearch.Sorting
        Dim eSortExp As String = e.SortExpression 'header name
        Dim eSortDir As String = e.SortDirection 'def = asc = 0, 1 = desc
        Dim ePageIndexChange = Session("PageIndex") 'pi chg?
        Dim dv As System.Data.DataView = New System.Data.DataView
        dv = CType(Session("gv"), System.Data.DataTable).DefaultView
        If ePageIndexChange = True Then
            Session("SearchSort") = eSortExp ' & " " & eSortDir
        Else 'sort true
            If e.SortDirection = 0 Then
                e.SortDirection = 1
            Else
                e.SortDirection = 0
            End If
            Session("SearchSort") = eSortExp ' & " " & eSortDir
        End If

        dv.Sort = CType(Session("SearchSort"), String)

        gvSearch.DataSource = dv
        gvSearch.DataBind()
    End Sub

• When it hits the bolded line, an "IndexOutofRangeException was unhandled by user code" occurs.
• Cannot find column Reference Number.
•  Reference Number is the name of the column I clicked on in the gridview data table.
• Any suggestions how I can pass the SortExpression/Direction in & pass d.Sort into gv.Bind?
• I think I'm close, just a little lost.
• Thank you in advance for prompt professional reply.

LiamHughes1981:

But because the sort script sorts the DataView of the GridView there is no information to access on what is sorted and in which direction.

Are you storing it in ViewState like in my example?

Coroebus:

line is : gridViewPublishers.DataSource = SortDataTable(Me.gridViewPublishers.DataSource, False)

At first glance everything looks fine. What changes have you made to my code? Also, take a look at the stack trace and perhaps step into the code to get an idea of what's going wrong.

maniac:

• When it hits the bolded line, an "IndexOutofRangeException was unhandled by user code" occurs.
• Cannot find column Reference Number.

Is Reference Number identical to what the name of the column is?

maniac:

Any suggestions how I can pass the SortExpression/Direction in & pass d.Sort into gv.Bind?

You could put it in the ViewState like in my original code.

StrongTypes:

Coroebus:

line is : gridViewPublishers.DataSource = SortDataTable(Me.gridViewPublishers.DataSource, False)

At first glance everything looks fine. What changes have you made to my code? Also, take a look at the stack trace and perhaps step into the code to get an idea of what's going wrong.

Hello,

I found the error : "Handles gridViewPublishers.Sorting" and "Handles gridViewPublishers.PageIndexChanging"

now, everything looks fine !

Thanks a lot four your code !