Making standard postback for exporting RadGrid with AjaxManager

[Tushar]

Hi,
I have implemented custom export functionality to export RadGrid data.
I have added a menu “Export All Columns” to HeaderContextMenu of Grid, which when clicked Grid data should be exported to CSV.

RadGrid is ajaxified using RadAjaxManager:
    <telerik:RadAjaxManager runat="server" ID="RadAjaxManager1" OnAjaxRequest="RadAjaxManager1_AjaxRequest">
        <telerik:AjaxSetting AjaxControlID="RadAjaxManager1">
            <UpdatedControls>
                    <telerik:AjaxUpdatedControl ControlID="PanelVendor" />
                    <telerik:AjaxUpdatedControl ControlID="pnlGrid" LoadingPanelID="RadAjaxLoadingPanel1" />
                <telerik:AjaxUpdatedControl ControlID="RadWindowManager1" />
            </UpdatedControls>
        </telerik:AjaxSetting>        <AjaxSettings>
        <telerik:AjaxSetting AjaxControlID="UsersGrid">
            <UpdatedControls>
                    <telerik:AjaxUpdatedControl ControlID="UsersGrid" />
            </UpdatedControls>
        </telerik:AjaxSetting>
        </AjaxSettings>
    </telerik:RadAjaxManager>

Following this link http://www.telerik.com/support/code-library/export-radgrid-content-to-excel-word-csv-pdf-with-ajax-enabled , I have added javascript code to disable ajax and make standard postback:
function onRadAjaxRequestStart(ajaxManager, eventArgs) {
    if (eventArgs.EventTargetElement.value != undefined && eventArgs.EventTargetElement.value.indexOf("Export") != -1) {
        eventArgs.set_enableAjax(false);
        ajaxManager.set_enableAJAX(false);
    }
}

Now this all works fine and data is exported to CSV when “Export All Columns” header menu is clicked.
But the RadAjaxLoadingPanel is displayed on the grid and it does not go away even after CSV is downloaded.

What do I need to do so that RadAjaxLoadingPanel does not appear while exporting?

[Konstantin Dikov]

Hi Tushar,

The Code-Library that you are referring to is a rather old and I strongly recommend that you take a look at the following help article, where detailed information for exporting from AJAX enabled RadGrid is available:

• Export from Ajaxified Grid

Furthermore, for your convenience, following is a very simple example demonstrating how to implement the approach from the help article:

<telerik:RadAjaxManager runat="server" ID="RadAjaxManager1" DefaultLoadingPanelID="LoadingPanel1">
    <AjaxSettings>
        <telerik:AjaxSetting AjaxControlID="RadGrid1">
            <UpdatedControls>
                <telerik:AjaxUpdatedControl ControlID="RadGrid1" />
            </UpdatedControls>
        </telerik:AjaxSetting>
    </AjaxSettings>
    <ClientEvents OnRequestStart="onRadAjaxRequestStart" />
</telerik:RadAjaxManager>

<telerik:RadAjaxLoadingPanel runat="server" Skin="Default" ID="LoadingPanel1"></telerik:RadAjaxLoadingPanel>

<telerik:RadCodeBlock runat="server">
    <script type="text/javascript">
        function onRadAjaxRequestStart(sender, args) {
            if (args.get_eventTarget().indexOf("ExportTo") >= 0)
                args.set_enableAjax(false);
        }
    </script>
</telerik:RadCodeBlock>

<telerik:RadGrid ID="RadGrid1" runat="server" OnNeedDataSource="RadGrid1_NeedDataSource">
    <MasterTableView CommandItemDisplay="Top" CommandItemSettings-ShowExportToCsvButton="true"></MasterTableView>
</telerik:RadGrid>

Finally, please inspect your page for any JavaScript errors when you try to export from the grid, which could prevent the proper work of the controls.

I hope this helps.


Regards,
Konstantin Dikov
Telerik

 

 

[Lenny_shp]

2015.2.908.45  RadGrid MasterTableView CommandItemSettings-ShowExportToExcelButton="true"​

args.get_eventTarget() returns "RadGrid1" when Export button is clicked and not any "ExportTo" button.

No difference with RadCodeBlock or RadScriptBlock.

[Lenny_shp]

I found that RadGrid1's ClientSetting OnCommand="CheckChanges" was preventing the ExportToExcelButton to be reflected in args.get_eventTarget.

Researching...

[Lenny_shp]

Same issue applies to RadAjaxPanel.   I saw some people having the same issue and don't see any resolution for this with the built-in Export Command when RadGrid OnCommand is used, args.get_eventTarget in OnRequestStart has "RadGrid1" instead of "ExportToExcel" button.

 Do we have to use external button outside of the grid to do the export??

[Konstantin Dikov]

Hi,

When you attach handler to the client-side OnCommand event of the grid, the commands mechanism will be changed and the postback will be initiated from the RadGrid. In order to handle that scenario you need to use global variable to determine if an Export command was fired:

<telerik:RadAjaxManager runat="server" ID="RadAjaxManager1" DefaultLoadingPanelID="LoadingPanel1">
    <AjaxSettings>
        <telerik:AjaxSetting AjaxControlID="RadGrid1">
            <UpdatedControls>
                <telerik:AjaxUpdatedControl ControlID="RadGrid1" />
            </UpdatedControls>
        </telerik:AjaxSetting>
    </AjaxSettings>
    <ClientEvents OnRequestStart="onRadAjaxRequestStart" />
</telerik:RadAjaxManager>

<telerik:RadAjaxLoadingPanel runat="server" Skin="Default" ID="LoadingPanel1"></telerik:RadAjaxLoadingPanel>

<telerik:RadCodeBlock ID="RadCodeBlock1" runat="server">
    <script type="text/javascript">
        var enableAjax = true;

        function onRadAjaxRequestStart(sender, args) {
            args.set_enableAjax(enableAjax);
            enableAjax = true;
        }

        function CheckChanges(sender, args) {
            if (args.get_commandName().indexOf("Export") >= 0) {
                enableAjax = false;
            }
        }
    </script>
</telerik:RadCodeBlock>

<telerik:RadGrid ID="RadGrid1" runat="server" OnNeedDataSource="RadGrid1_NeedDataSource">
    <MasterTableView CommandItemDisplay="Top" CommandItemSettings-ShowExportToCsvButton="true"></MasterTableView>
    <ClientSettings>
        <ClientEvents OnCommand="CheckChanges" />
    </ClientSettings>
</telerik:RadGrid>

Hope this helps.


Regards,
Konstantin Dikov
Telerik

[Lenny_shp]

Konstantin,

Using a global variable worked, thank you!