ASPxClientGanttCustomCommandEventArgs Class

<dx:ASPxGantt ID="Gantt" ClientInstanceName="clientGantt" >
    <SettingsToolbar>
        <Items>
            <dx:GanttCustomToolbarItem Checked="True" Text="Show Resources" CommandName="Toggle" />
        </Items>
    </SettingsToolbar>
    <ClientSideEvents CustomCommand="function(s, e) {
        if(e.commandName == 'Toggle') {
            gantt.ShowResources(e.parameter);
        }
    } />
</dx:ASPxGantt>