问MVC Telerik网格-取消更新AJAX请求

EN

@(Html.Telerik().Grid(Model).Name("DistributionGrid").DataKeys(dataKeys => dataKeys.Add("DistributionID")).
                                                ToolBar(toolBar => toolBar
                      .Template(@<text>
                                @{ 
                                    <b>Distribution</b>
                                    <ul class='ul-bulk-menu'>
                                        <li><button id='newDistribution' class='t-button t-button-icon' title='New Distribution'><span>Add Distribution</span></button></li>
                                    </ul>
                                  }

                            </text>))

                                        .Columns(c =>
                                        {
                                            c.Command(command =>
                                            {
                                                command.Edit().ButtonType(GridButtonType.Image).HtmlAttributes(new { title = "Edit Distribution"});
                                                command.Delete().ButtonType(GridButtonType.Image).HtmlAttributes(new { title = "Delete Distribution" });
                                            }).Width(100);

                                            c.Bound(o => o.DistTo);
                                            c.Bound(o => o.DistCC);

                                        })

                                        .Scrollable(o => o.Height(440))
                                        .Resizable(o => o.Columns(true))
                                        .Reorderable(o => o.Columns(true))

                                        .DataBinding(o => o.Ajax()
                                            .Select("SelectDist", "Mail")
                                            .Update("UpdateDist", "Mail")
                                            .Delete("DeleteDist", "Mail")
                                            )

                                        .Editable(editing => editing.Mode(GridEditMode.InForm))
                                        .ClientEvents(events => events.OnCommand("Grid_OnRequestStart"))
                                    ) 
</div>

function Grid_OnRequestStart(e) {
    if (e.name == "update") {
        alert(e.dataItem.DistTo + " - " + $("#DistTo").val());
        if (confirm("Are you sure?")) {
            alert("Distribution was updated!");
        }
        else {
        // Here I want to cancel the update request
        }
    }
}