Gridview Header trier

Bonjour,

J'ai un gridview et je souhaite mettre des images pour trier certaines colonnes, j'arrive à mettre une image pour trier mais l'image n'est pas cliquable donc ne lance pas le script.
ci-joint mon script sur gridview_rowcreated:

protectedvoid GridView1_RowCreated(object sender, GridViewRowEventArgs e){

if ((e.Row != null) && e.Row.RowType == DataControlRowType.Header) {
   foreach (TableCell cell in e.Row.Cells) { 
         if (cell.Controls.Count > 0) { 
               LinkButton button = cell.Controls[0] asLinkButton; 
               if (button != null) { 
                        Image image = newImage(); 
                        image.ImageUrl = "images/calendrierX.gif";
                  if (GridView1.SortExpression == button.CommandArgument){
                           if (GridView1.SortDirection == SortDirection.Ascending)
                                 image.ImageUrl = "images/calendrier1.gif";
                           else 
                                 image.ImageUrl = "images/calendrier2.gif"; 
                           } cell.Controls.Add(image); 
                  }
                } 
               } 
            }
}

<asp:GridViewID="GridView1"runat="server"AutoGenerateColumns="False"DataMember="DefaultView"DataSourceID="XXXXX"CellPadding="2"ForeColor="#333333"GridLines="None"AllowPaging="True"Font-Names="Arial"Font-Size="Small"DataKeyNames="IdX"OnRowDeleting="GridView1_RowDeleting"PageSize="30"BorderColor="#8080FF"BorderWidth="2px"CellSpacing="1"AllowSorting="True"OnRowCreated="GridView1_RowCreated">
Merci

fred

utilise les templates et ne fais pas ça en code behind.

<

Columns>

   <asp:TemplateField>

      <HeaderTemplate>

         <asp:LinkButtonID="LinkButton1"runat="server"> <!--Tu lies ton evenement qui modifie le sens du tri avec ce bouton là-->

            <imgsrc="urldetonimage"alt="altdetonimage"/>

      </asp:LinkButton>

   </HeaderTemplate>

   <ItemTemplate>

      <asp:LabelID="lblData"runat="server"Text='<%# Bind("tonchamp") %>'/>

   </ItemTemplate>

</asp:TemplateField>

</Columns>