c# - All GridView rows disappear while selecting a row -

please consider values in comments got in debug mode:

protected void filesgrid_selectedindexchanged(object sender, eventargs e) {     int selected = filesgrid.selectedindex; // selected = 2     filesgrid.databind();  //added after feedback in comments. makes no change     int count = filesgrid.rows.count; // count = 0     gridviewrow row = filesgrid.rows[selected]; // row = null     gridviewrow row0 = filesgrid.rows[0]; // row = null } 

i came code while investigating why selectedvalue gives null in event handler (the datakeynames parameter set sure).

can explain how possible?

thank in advance.

ps. here aspx code:

<asp:gridview id="filesgrid" runat="server" autogeneratecolumns="false"      autogenerateselectbutton="true"       onselectedindexchanged="filesgrid_selectedindexchanged"      style="margin-top: 0px" >     <columns>         <asp:commandfield showdeletebutton="true" />         <asp:boundfield datafield="name" headertext="name" />         <asp:boundfield datafield="length" dataformatstring="{0:n0}"              headertext="size in bytes" htmlencode="false" />     </columns> </asp:gridview> 

here how bind data:

protected void page_load(object sender, eventargs e) {     if (!page.ispostback)     {         string [] dd = {"fullname"};         filesgrid.datakeynames = dd;          string apppath = request.physicalapplicationpath;          directoryinfo dirinfo = new directoryinfo(apppath);          fileinfo[] files = dirinfo.getfiles();         filesgrid.datasource = files;         filesgrid.databind();            }  } 

y copy pasted code, delete line filesgrid.databind() in filesgrid_selectedindexchanged, see 2 methods not posting, aren't in code posted onselectedindexchanging, onrowdeleting events, comment them aspx , see if works, or se if events not doing tricking, deleting rows in gridview.

tell me if works

i did this

  protected void page_load(object sender, eventargs e)     {         if (!page.ispostback)         {             string[] dd = { "fullname" };             filesgrid.datakeynames = dd;              string apppath = request.physicalapplicationpath;             directoryinfo dirinfo = new directoryinfo(apppath);             fileinfo[] files = dirinfo.getfiles();             filesgrid.datasource = files;             filesgrid.databind();         }     }     protected void filesgrid_selectedindexchanged(object sender, eventargs e)     {         int selected = filesgrid.selectedindex; // selected = 2         //filesgrid.databind();  //added after feedback in comments. makes no change         int count = filesgrid.rows.count; // count = 0         gridviewrow row = filesgrid.rows[selected]; // row = null         gridviewrow row0 = filesgrid.rows[0]; // row = null     }     protected void filesgrid_rowdeleting(object sender, gridviewdeleteeventargs e)     {      }     protected void filesgrid_selectedindexchanging(object sender, gridviewselecteventargs e)     {      } 

the aspx code.

<asp:scriptmanager id="scriptmanager1" runat="server" enablescriptglobalization="true"             asyncpostbacktimeout="0" enablescriptlocalization="true">         </asp:scriptmanager>         <asp:updatepanel id="uppanel" runat="server">             <contenttemplate>                         <asp:gridview id="filesgrid" runat="server" autogeneratecolumns="false" autogenerateselectbutton="true"                     onrowdeleting="filesgrid_rowdeleting" onselectedindexchanged="filesgrid_selectedindexchanged"                     style="margin-top: 0px" onselectedindexchanging="filesgrid_selectedindexchanging">                     <columns>                         <asp:commandfield showdeletebutton="true" />                         <asp:boundfield datafield="name" headertext="name" />                         <asp:boundfield datafield="length" dataformatstring="{0:n0}" headertext="size in bytes"                             htmlencode="false" />                     </columns>                 </asp:gridview>             </contenttemplate>                  </asp:updatepanel>