KeyLimeTie Blog

How to Communicate between ASP.NET and Flash
By Brian Pautsch – 12/18/2007 11:29:46 PM. Posted to Code Snippets.

Ever wonder how to send data back and forth between ASP.NET and Flash?

About a year ago, we designed and built the DIY Floor Plan website (http://www.diyfloorplan.com). We needed the ability to send data between the Flash Floor Plan Designer and the ASP.NET web pages that saved the data to the database. We wanted the floor plan designer to be as "dumb" as possible...simply design the floor plan and allow the ASP.NET application manage the data. Here's some quick code snippets that will show you how to do it very easily.

ViewFloorPlan.aspx
This page displays the public, non-editable version of the floor plan. The important thing here is that we put the Floor Plan GUID in a Flash Parameter. We use a GUID to prevent users from seeing floor plans that are not publicly available by the floor plan administrator. The Flash application uses the GUID as the key to communicate with the ASP.NET application.

1<script type="text/javascript">
2    var so = new SWFObject("/flash/map_client.swf", "map_client", "775", "650", "6", "#ececec");
3    so.addParam("menu", "false");
4    so.addParam("quality", "high");
5    so.addParam("wmode", "transparent");
6    so.addParam("allowScriptAccess", "sameDomain");
7    so.addParam("movie", "/flash/map_client.swf");
8    so.addParam("bgcolor", "#ffffff");
9    so.addParam("FlashVars", "FloorPlanGUID=<% GetFloorPlanGUID(); %>");
10    so.write("flashcontent1");
11</script>

FlashGetData.aspx
This page is used by the Flash application to get data. The ASPX portion of this web page has no HTML or controls. When processing the Flash application's request, we output the data it needs in the HTML in a name-value pair. A little explanation...this page is called for the floor plan XML or an individual booth's details (name, address, etc.). After calling the database to get the data, it's written to the output HTML as field=value.

1public partial class FlashGetData : System.Web.UI.Page
2{
3protected void Page_Load(object sender, EventArgs e)
4    {
5       if (Request.QueryString["Mode"] != null)
6        {
7            try
8            {
9                //Extract mode
10                Enums.ModeEnum mode = 
                           (Enums.ModeEnum)int.Parse(Request.QueryString["Mode"].ToString());
11
12                //Process based on mode
13                DataSet ds = null;
14                DataRow row;
15                if (mode == Enums.ModeEnum.RequestFloorPlan)
16                {
17                    //Extract Querystring parameters
18                    string floorPlanGUID = Request.QueryString["FloorPlanGUID"].ToString();
19
20                    //Get the data
21                    ds = FloorPlans_BLL.SelectFloorPlansByFloorPlanGUID(new Guid(floorPlanGUID));
22                    row = ds.Tables[0].Rows[0];
23                    Response.Write("FloorPlanXML=" + row["FloorPlanXML"].ToString());
24                }
25                else if (mode == Enums.ModeEnum.RequestCompanyDetails)
26                {
27                    //Extract Querystring parameters
28                    string floorPlanGUID = Request.QueryString["FloorPlanGUID"].ToString();
29                    string boothID = Request.QueryString["BoothID"].ToString();
30
31                    //Get the data
32                    ds = Companies_BLL.SelectCompaniesByFloorPlanIDBoothID(
                               new Guid(floorPlanGUID), boothID);
33                    Response.Write("CompanyDetails=" + BuildCompanyDetails(boothID, ds));
34                }
35            }
36            catch (Exception ex)
37            {
38                Helpers.ProcessException(ex);
39            }
40        }
41    }
42}

FlashSaveData.aspx
This page is used in the administration area. Again, the ASPX portion of this web page has no HTML or controls.
The Flash movie executes a command like: xmlDoc.sendAndLoad("FlashSaveData.aspx?FloorPlanGUID=xxx-xxx-xxx-xxx", returnXML, "POST");
The important point of this code is Line 19. The Flash application posts data in the Request stream.

1public partial class FlashSaveData : System.Web.UI.Page
2{
3protected void Page_Load(object sender, EventArgs e)
4    {
5        //The Flash movie executes a command like:
6        //xmlDoc.sendAndLoad("FlashSaveData.aspx?FloorPlanGUID=xxx-xxx-xxx-xxx", 
                   returnXML, "POST");
7
8         XmlDocument doc = null;
9         FloorPlans floorplans = null;
10        FloorPlanCompanies fpc = null;
11        DataSet ds = null;
12        try
13        {
14            if (Request.QueryString["FloorPlanGUID"] != null)
15            {
16                //Extract GUID and XML
17                string floorPlanGUID = Request.QueryString["FloorPlanGUID"].ToString();
18                doc = new XmlDocument();
19                doc.Load(Request.InputStream);
20
21                //Get the FloorPlan row
22                ds = FloorPlans_BLL.SelectFloorPlansByFloorPlanGUID(new Guid(floorPlanGUID));
23                DataRow row = ds.Tables[0].Rows[0];
24
25                //Build FloorPlans object
26                floorplans = new FloorPlans();
27                floorplans.FloorPlanID = Int32.Parse(row["FloorPlanID"].ToString());
28                floorplans.FloorPlanGUID = new Guid(row["FloorPlanGUID"].ToString());
29                floorplans.UserID = Int32.Parse(row["UserID"].ToString());
30                floorplans.Title = row["Title"].ToString();
31                floorplans.URL = row["URL"].ToString();
32                floorplans.FloorPlanXML = doc.InnerXml;
33                floorplans.Active = (bool)row["Active"];
34                floorplans.RewriterID = Int32.Parse(row["RewriterID"].ToString());
35
36                //Make sure all booths are now in the database
37                XmlNodeList objNodes = doc.SelectNodes("./floorplan/booths/boothtxt");
38                foreach (XmlNode objNode in objNodes)
39                {
40                    fpc = new FloorPlanCompanies();
41                    fpc.FloorPlanID = Int32.Parse(row["FloorPlanID"].ToString());
42                    fpc.BoothID = objNode.InnerXml;
43                    fpc.CompanyID = 0;
44                    FloorPlanCompanies_BLL.SaveFloorPlanCompanies(fpc, false, null);
45                }
46
47                //Save to database
48                FloorPlans_BLL.UpdateFloorPlans(floorplans);
49            }
50            else
51                throw new Exception("FloorPlanGUID missing");
52        }
53        catch (Exception ex)
54        {
55            Helpers.ProcessException(ex);
56        }
57        finally
58        {
59            if (ds != null)
60            {
61                ds.Dispose();
62                ds = null;
63            }
64            fpc = null;
65            floorplans = null;
66            doc = null;
67        }
68    }
69}