Niranjan Singh's coding blog

Scenario:

DevExpress Web controls generates callback to refresh the controls and pass data between events. When we using some Callback panel or ASPxGridView callbacks event methods then we cannot call Respose.Redirect method to navigate between pages. If we use these methods then it will raise exception.

Solution:

To avoid these exception use the ASPxWebControl.RedirectOnCallback method to rather than pages.Response.Redirect() because it does not work in a callback. Let you have created a callback with “MYCallback_Callback” event handler method then at the callback method you should use below ASPxWebControl.RedirectOnCallback method to redirect on another page.

DevExpress.Web.ASPxClasses.ASPxWebControl.RedirectOnCallback("~/MyPage.aspx?id="+ e.Parameter);

You will not be able to use Response.Redirect () or Server.Transfer () in a callback to check if the control has a client event can be used instead, if this event can use window.location.replace("MyPage.aspx"), using JavaScript on the client to move to another page.

In the ASPxHyperLink.Init handler, you can use the ASPxGridView.GetDetailRowKeyValue method with ASPxHyperLink.NamingContainer property as a parameter, to get the main grid row key value.

[C#]

protected void ASPxHyperLink1_Init(object sender, EventArgs e) {
ASPxHyperLink myLink =(ASPxHyperLink)sender;
int key = Convert.ToInt32(ASPxGridView.GetDetailRowKeyValue(myLink.NamingContainer));
}

It would be better to use a binding-expression for the ASPxHyperLink.NavigateUrl property in the .ASPX file.

[ASPx]

<EmptyDataRow>
<dx:ASPxHyperLink ID="ASPxHyperLink1" runat="server" Text="ASPxHyperLink"
NavigateUrl="<%# ASPxGridView.GetDetailRowKeyValue(Container) %>" />
</EmptyDataRow>

The ASPxGridView is a server side control, so it renders on the server side.

If you know how the summary value should be changed using the client side code, you need to do the following:

1) add the ASPxLabel to the column's FooterTemplate container and set its ClientInstanceName to a some value, for example, lblFooter;
2) use the lblFooter.SetText('some text') to change the displayed summary value.

Here is some sample code:

[ASPx]

<dx:GridViewDataTextColumn FieldName="CategoryID" ReadOnly="True" VisibleIndex="1">
<EditFormSettings Visible="False" />
<FooterTemplate>
<dx:ASPxLabel ID="ASPxLabel1" ClientInstanceName ="lblFooter" runat="server"
Text="<%# GetSummaryValue(Container)%>">
</dx:ASPxLabel>
</FooterTemplate>
</dx:GridViewDataTextColumn>
....

[C#]

protected string GetSummaryValue(GridViewFooterCellTemplateContainer container) {
ASPxGridView gridView = container.Grid;
GridViewDataColumn column = container.Column as GridViewDataColumn;
if(column == null)
return string.Empty;
for(int i = 0; i < gridView.TotalSummary.Count; i ++)
if(gridView.TotalSummary[i].FieldName == column.FieldName) {
return gridView.GetTotalSummaryValue(gridView.TotalSummary[i]).ToString();
}
return string.Empty;
}

Create a Class that inherits ITemplate and add controls the container ; you want to add.
Assign the object of that class to ASPxGridView's Templates.FooterRow property as:

ASPxGridView1.Templates.FooterRow = new CustomFooterRowTemplate();

public class CustomFooterRowTemplate: ITemplate
{            
     void ITemplate.InstantiateIn(Control container)
     {
         Button button = new Button();
         button.Text = "Test"; 
         container.Controls.Add(button);
     }
}