NavHistory.cs

public class NavHistory : Control
{
    private readonly List<Tuple<string, Action<string>>> _setters = new List<Tuple<string, Action<string>>>();
    private Dictionary<string, string> _changes = new Dictionary<string, string>();
    private ScriptManager _sm;

    protected override void OnInit(EventArgs e)
    {
        base.OnInit(e);
        Page.Init += Page_Init;
        Page.Items[typeof(NavHistory)] = this;
    }

    protected override void LoadViewState(object savedState)
    {
        _changes = (Dictionary<string, string>)savedState;
    }

    protected override object SaveViewState()
    {
        return _changes;
    }

    private void Page_Init(object sender, EventArgs e)
    {
        _sm = ScriptManager.GetCurrent(Page);
        if (_sm != null) _sm.Navigate += Navigate;
    }

    public static NavHistory GetCurrent(Page page)
    {
        if (page == null)
            throw new ArgumentNullException("page");
        return page.Items[typeof(NavHistory)] as NavHistory;
    }

    private void Navigate(object sender, HistoryEventArgs e)
    {
        List<string> changed = new List<string>();

        Page.Trace.Write("NH.Navigate", e.State.DumpToString());
        foreach (string key in e.State)
        {
            string value = e.State[key];
            if (_changes.Any(a => a.Key == key && a.Value == value))
                break;
            _changes[key] = value;
            changed.Add(key);
        }

        foreach (var a in _setters)
            if (changed.Contains(a.Item1))
                a.Item2(_changes[a.Item1]);
    }

    private void AddHistoryValue(string key, string value)
    {
        if (!_sm.IsInAsyncPostBack) return;
        _changes[key] = value;
        foreach (var pair in _changes)
            _sm.AddHistoryPoint(pair.Key, pair.Value);
    }

    private static string Key(Control c)
    {
        return c.ClientID;
    }

    public void Wire(string name, RadComboBox c, Action<string> action = null)
    {
        if (c == null) throw new ArgumentNullException("c");
        Page.Trace.Write("NH.Wire", c.ID);
        var key = name ?? Key(c);
        c.SelectedIndexChanged += (o, args) => AddHistoryValue(key, c.Text);
        _setters.Add(new Tuple<string, Action<string>>(key, a =>
            {
                c.SelectedValue = c.Text = a;
            }));
        if (action != null) _setters.Add(new Tuple<string, Action<string>>(key, action));
    }

    public void Wire(string name, RadioButtonList c, Action<string> action = null)
    {
        if (c == null) throw new ArgumentNullException("c");
        Page.Trace.Write("NH.Wire", c.ID);
        var key = name ?? Key(c);
        c.SelectedIndexChanged += (o, args) => AddHistoryValue(key, c.SelectedIndex.ToString());
        _setters.Add(new Tuple<string, Action<string>>(key, a => c.SelectedIndex = a.ToNullableInt32().GetValueOrDefault(-1)));
        if (action != null) _setters.Add(new Tuple<string, Action<string>>(key, action));
    }

    public void Wire(string name, CheckBoxList c, Action<string> action = null)
    {
        if (c == null) throw new ArgumentNullException("c");
        Page.Trace.Write("NH.Wire", c.ID);
        var key = name ?? Key(c);
        c.SelectedIndexChanged += (o, args) => AddHistoryValue(key, c.SelectedIndex.ToString());
        _setters.Add(new Tuple<string, Action<string>>(key, a => c.SelectedIndex = a.ToNullableInt32().GetValueOrDefault(-1)));
        if (action != null) _setters.Add(new Tuple<string, Action<string>>(key, action));
    }

    public void Wire(string name, CheckBox c, Action<string> action = null)
    {
        if (c == null) throw new ArgumentNullException("c");
        Page.Trace.Write("NH.Wire", c.ID);
        var key = name ?? Key(c);
        c.CheckedChanged += (o, args) => AddHistoryValue(key, c.Checked.ToString());
        _setters.Add(new Tuple<string, Action<string>>(key, a => c.Checked = a.ToNullableBool().GetValueOrDefault(false)));
        if (action != null) _setters.Add(new Tuple<string, Action<string>>(key, action));
    }

    public void Wire(string name, RadButton c, Action<string> action = null)
    {
        if (c == null) throw new ArgumentNullException("c");
        Page.Trace.Write("NH.Wire", c.ID);
        var key = name ?? Key(c);
        c.Click += (o, args) => AddHistoryValue(key, "Clicked");
        if (action != null) _setters.Add(new Tuple<string, Action<string>>(key, action));
    }

    public void Wire(string name, RadTextBox c, Action<string> action = null)
    {
        if (c == null) throw new ArgumentNullException("c");
        Page.Trace.Write("NH.Wire", c.ID);
        var key = name ?? Key(c);
        c.TextChanged += (o, args) => AddHistoryValue(key, c.Text);
        _setters.Add(new Tuple<string, Action<string>>(key, a => c.Text = a));
        if (action != null) _setters.Add(new Tuple<string, Action<string>>(key, action));
    }

    public void Wire(string name, RadTabStrip c, Action<string> action = null)
    {
        if (c == null) throw new ArgumentNullException("c");
        Page.Trace.Write("NH.Wire", c.ID);
        var key = name ?? Key(c);
        c.TabClick += (o, args) => AddHistoryValue(key, c.SelectedIndex.ToString());
        _setters.Add(new Tuple<string, Action<string>>(key, a => c.SelectedIndex = a.ToNullableInt32().GetValueOrDefault(-1)));
        if (action != null) _setters.Add(new Tuple<string, Action<string>>(key, action));
    }

    public void Wire(string name, RadGrid c)
    {
        if (c == null) throw new ArgumentNullException("c");
        Page.Trace.Write("NH.Wire", c.ID);
        var keyZ = (name ?? Key(c)) + "_z";
        var keyS = (name ?? Key(c)) + "_s";
        var keyP = (name ?? Key(c)) + "_p";
        c.PageIndexChanged += (o, args) => AddHistoryValue(keyP, args.NewPageIndex.ToString());
        c.PageSizeChanged += (o, args) => AddHistoryValue(keyZ, args.NewPageSize.ToString());
        c.SortCommand += (o, e) => AddHistoryValue(keyS, e.NewSortOrder.ToString() + "|" + e.SortExpression);
        _setters.Add(new Tuple<string, Action<string>>(keyP, a => c.CurrentPageIndex = a.ToNullableInt32().GetValueOrDefault(0)));
        _setters.Add(new Tuple<string, Action<string>>(keyZ, a => c.PageSize = a.ToNullableInt32().GetValueOrDefault(25)));
        _setters.Add(new Tuple<string, Action<string>>(keyS, a => SetSort(c, a)));
    }

    private static void SetSort(RadGrid radGrid, string s)
    {
        string[] parts = s.Split('|');
        radGrid.MasterTableView.SortExpressions.AddSortExpression(new GridSortExpression { FieldName = parts[1], SortOrder = StringExtensions.ChangeType<GridSortOrder>(parts[0]) });
        radGrid.Rebind();
    }
}