ASP.NET Podcast Show #119 - Using the History (Back) Functionality with the ASP.NET AJAX Web Services in .NET 3.5 Service Pack 1 Beta 1

Subscribe to Everything.

Original Url: http://aspnetpodcast.com/CS11/blogs/asp.net_podcast/archive/2008/07/01/asp-net-podcast-show-119-using-the-history-back-functionality-with-the-asp-net-ajax-web-services-in-net-3-5-service-pack-1-beta-1.aspx

Subscribe to WMV format.

Subscribe to M4V for iPod Users.

Subscribe to MP3 (Audio only).

Download WMV.

Download M4V for iPod Users.

Download MP3 (Audio only).

Download PPT associated file.

Download Source Code.

Show Notes:

Source Code:

     <asp:ScriptManager ID="sm" runat="server"
        EnableHistory="true"
        EnableSecureHistoryState="true" >
        <Services>
            <asp:ServiceReference Path="~/GetMaps.asmx" />
        </Services>
    </asp:ScriptManager>
<script language="javascript" type="text/javascript">
    var Map;
    var userNavigated = false;
    function pageLoad() {
        Sys.Application.add_navigate(onNavigate);

        GetMaps.MapData(SetupMap);

    }

    function onNavigate(sender, e) {
        if (userNavigated) {
            restorePage(e.get_state());
        }
    }

    function restorePage(PageState) {
        var UpperLeftLat = new Number(PageState.UpperLeftLat);
        var UpperLeftLon = new Number(PageState.UpperLeftLon);
        var BottomRightLat = new Number(PageState.LowerRightLat);
        var BottomRightLon = new Number(PageState.LowerRightLon);
        var ZoomLevel = new Number(PageState.ZoomLevel);
        var Lat = (UpperLeftLat + BottomRightLat ) / 2;
        var Lon = (UpperLeftLon + BottomRightLon) / 2;

        if (!(isNaN(Lat) || isNaN(Lon))) {
            Map.LoadMap(new VELatLong(Lat, Lon), ZoomLevel, 'h', false);
            GetMaps.GetPointData(10, UpperLeftLat, UpperLeftLon,
            BottomRightLat, BottomRightLon, GetDataSuccess);
        }
    }

    function SetupMap(result) {
        var Lat = result.Center.Lat;
        var Lon = result.Center.Lon;
        var ZoomLevel = result.ZoomLevel;
        var MapView, TopLeft, BottomRight;
        try {
            Map = new VEMap('MapDiv');
            Map.LoadMap(new VELatLong(Lat, Lon), ZoomLevel, 'h', false);
            MapView = Map.GetMapView();
            TopLeft = MapView.TopLeftLatLong;
            BottomRight = MapView.BottomRightLatLong;
            //TopleftLatLong and BottomRightLatLong return a VELatLong object.
            Map.AttachEvent("onchangeview", MapChangedView);
            SetupHistory();
            GetMaps.GetPointData(10, TopLeft.Latitude, TopLeft.Longitude,
                BottomRight.Latitude, BottomRight.Longitude, GetDataSuccess);
        }
        catch (e) {
            alert("Error: " + e);
        }
    }
    function GetDataSuccess(result) {
        var i = 0;
        var Lat, Lon;
        for (i = 0; i < result.length; i++) {
            Lat = result[i].Location.Lat;
            Lon = result[i].Location.Lon;
            var shape = new VEShape(VEShapeType.Pushpin, new VELatLong(Lat, Lon));
            shape.SetTitle("Title: " + i);
            shape.SetDescription(result[i].Description);
            Map.AddShape(shape);
        }
    }

    function SetupHistory() {
        var PageTitle;
        var now = new Date();
        var CurrentTime = now.getHours() + ":" + now.getMinutes() + ":" + now.getSeconds();
        PageTitle = "AJAX History Test Time:" + CurrentTime;
        MapView = Map.GetMapView();
        TopLeft = MapView.TopLeftLatLong;
        BottomRight = MapView.BottomRightLatLong;
        ZoomLevel = Map.GetZoomLevel();
        var PageState =
        {
            "UpperLeftLat": TopLeft.Latitude,
            "UpperLeftLon": TopLeft.Longitude,
            "LowerRightLat": BottomRight.Latitude,
            "LowerRightLon": BottomRight.Longitude,
            "ZoomLevel": ZoomLevel
        }
        userNavigated = false;
        Sys.Application.addHistoryPoint(PageState, PageTitle);
        userNavigated = true;
    }
    function MapChangedView(e) {
        
        Map.DeleteAllShapes();
        MapView = Map.GetMapView();
        TopLeft = MapView.TopLeftLatLong;
        BottomRight = MapView.BottomRightLatLong;
        SetupHistory();

        GetMaps.GetPointData(10, TopLeft.Latitude, TopLeft.Longitude,
        BottomRight.Latitude, BottomRight.Longitude, GetDataSuccess);
        
    }


</script>
    <div id="MapDiv" style="position:relative; width:450px; height: 350px;" ></div>

No Comments