title: Object reference not set to an instance of an object
body: <p>i am stuck with this error since last few hours.. i dont know what am i doing wrong here.. </p>
  
  <pre><code>    &lt;script type="text/javascript"&gt;
      function viewProfile(index)
      {
          var GridID = document.getElementById("PersonGridView");
          var row=GridID.rows[parseInt(index)+1];
          window.open('detailsid.aspx?'+row);
      }
      &lt;/script&gt;
  </code></pre>
  
  <p>
      
      
          
              </p>
  
  <pre><code>        &lt;Columns&gt;
              &lt;asp:BoundField HeaderText="First Name" DataField="FirstName" /&gt;
              &lt;asp:BoundField HeaderText="Last Name" DataField = "LastName" /&gt;
              &lt;asp:BoundField HeaderText="HomePhoneNumber" DataField="HomePhoneNumber" /&gt;
              &lt;asp:TemplateField HeaderText="ViewDetails"&gt;
              &lt;ItemTemplate&gt;
              &lt;asp:Button ID="Deatils" runat="server" Text="Details" /&gt;
              &lt;/ItemTemplate&gt;    
  
              &lt;/asp:TemplateField&gt;
  
              &lt;asp:TemplateField HeaderText="Actions"&gt;
              &lt;ItemTemplate&gt;
              &lt;asp:Button ID="Modify" runat="server" Text="Modify" /&gt;
              &lt;asp:Button ID="Delete" runat="server" Text="Delete" /&gt;
  
              &lt;/ItemTemplate&gt;
              &lt;/asp:TemplateField&gt;
  
  
          &lt;/Columns&gt;
  
  
          &lt;FooterStyle BackColor="#CCCC99" /&gt;
          &lt;PagerStyle BackColor="#F7F7DE" ForeColor="Black" HorizontalAlign="Right" /&gt;
          &lt;SelectedRowStyle BackColor="#CE5D5A" Font-Bold="True" ForeColor="White" /&gt;
          &lt;HeaderStyle BackColor="#6B696B" Font-Bold="True" ForeColor="White" /&gt;
          &lt;AlternatingRowStyle BackColor="White" /&gt;
      &lt;/asp:GridView&gt;
  &lt;/div&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p></p>
  
  <pre><code>&lt;p&gt; Code Behind : 
  protected void PersonGridView_RowDataBound(object sender, GridViewRowEventArgs e)
          {
  
                 if (e.Row.RowType == DataControlRowType.DataRow)
              {
           var ID = PersonGridView.DataKeys[e.Row.RowIndex]["ID"].ToString();
  
                  Button btnDetails = (Button)FindControl("Details");
                  Button btnModify = (Button)FindControl("Modify");
                  Button btnDelete = (Button)FindControl("Delete");
                  btnModify.CommandName = "Modify";
                  btnDelete.CommandName = "Delete";
                  btnDetails.CommandName = "Details";
                  btnDelete.CommandArgument = btnModify.CommandArgument = string.Format("{0}", ID);
                  btnDetails.Attributes["onclick"] = string.Format("viewProfile({0}); return false;", ID);
  
  
              }
          }
  </code></pre>