Question

How to fix it?

I declared handlers in Page_Load, Page_PreRender and markup. It doesn’t work normaly.

Code:

<asp:GridView ID="tableResults" runat="server" DataMember="Table" EnableModelValidation="True"
    CssClass="GridViewStyle" OnRowDeleting="dataViewRowDeleting" AutoGenerateDeleteButton="True">
    <HeaderStyle CssClass="GridViewHeaderStyle" />
    <RowStyle CssClass="GridViewRowStyle" />
    <Columns>
        <asp:TemplateField>
            <ItemTemplate>
                <asp:HyperLink ID="HyperLink1" runat="server" Text="Скачать объект" NavigateUrl='<%#"objects/" + Eval("Идентификатор") %>'></asp:HyperLink>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>

Handlers:

tableResults.AutoGenerateEditButton = true;
tableResults.RowEditing += new GridViewEditEventHandler(tableResults_RowEditing);
tableResults.RowUpdating += new GridViewUpdateEventHandler(tableResults_RowUpdating);
tableResults.RowCancelingEdit += new GridViewCancelEditEventHandler(tableResults_RowCancelingEdit);

Answer 1

Alright I tried your code and got the same issue as you. The reason is because you are manually calling Databind in Page_Load but you are not reattaching the datasource. You need reattach your datasource in your edit event handler (as well as other event handlers).

protected void tableResults_RowEditing(object sender, GridViewEditEventArgs e)
{
    tableResults.EditIndex = e.NewEditIndex;
    PopulateTableResults();   // In this method I attach the datasource and bind
}    

If you don’t want to do it manually you need to use the data source control.