c# - How to export selected data from my ASPx DevExpress gridview -

i need export xls selected row of devexpress gridview. when try export grid, creates empty file. think due callback clear data in grid before exporting.

this samples of aspx page.

the load data button

 <asp:imagebutton id="imagebutton1" runat="server" imageurl="~/styles/images/load.png" onclick="imagebutton1_click" /> 

the gridview

<dx:aspxgridview id="grid" clientinstancename="grid" runat="server" autogeneratecolumns="false" keyfieldname="car">         <columns>             <dx:gridviewcommandcolumn showselectcheckbox="true" visibleindex="0" caption="">             </dx:gridviewcommandcolumn>             <dx:gridviewdatatextcolumn caption="category" visibleindex="1" fieldname="category"                 name="category" groupindex="0" sortindex="0" sortorder="ascending">             </dx:gridviewdatatextcolumn>             <dx:gridviewdatatextcolumn caption="car" visibleindex="2" fieldname="car" name="car">             </dx:gridviewdatatextcolumn>         </columns>         <settingspager pagesize="100">         </settingspager>         <settings showfooter="true" />          <groupsummary>             <dx:aspxsummaryitem fieldname="car" summarytype="count" />         </groupsummary>      </dx:aspxgridview> 

the gridexporter

    <dx:aspxgridviewexporter id="gridexport" runat="server" gridviewid="grid" exportedrowtype="selected" /> 

the create file button

<dx:aspxbutton id="createfile" runat="server" text="create file"      usesubmitbehavior="false" onclick="createfile_click">                     <image url="~/styles/images/save.png">                     </image>     </dx:aspxbutton> 

now code behind.

when click load button, create fake datas tests.

    protected void imagebutton1_click(object sender, imageclickeventargs e)     {         createfakedata();     } 

i create datas in datatable object. , bind datatable grid.

grid.datasource = fakes; grid.databind(); 

everything seem works great when click export button, nothing exported.

    protected void createfile_click(object sender, eventargs e)     {         gridexport.writexlstoresponse();     } 

i followed devexpress tutoria export selected rows in aspl. seems page refreshed loose data binded grid before export.

i had similar situation when binding data aspxgridview in code behind. able solve rebinding in button click, before export line.

protected void createfile_click(object sender, eventargs e) {     grid.datasource = fakes;             grid.databind();             gridexport.writexlstoresponse(); }