If you follow Willy’s blog you would have seen a post mentioning I have been a busy little person recently (if you hadn’t see it you can go here to read it). One of the things about SAArchitect.net is that it does not run on the big boys edition of SharePoint, it actually runs on WSS. However the thing people commonly forget about WSS is that it actually can do everything it’s brother can do, it just does not have all the templates and the fiddly bits out of the box. This means the time/cost/pain to get to the same point as it’s brother is a bit/minor/average/excessively more. One of the fiddly little bits which is missing, is audience targeting. Which I think is super sexy for public web sites, especially when you want to show different things to users who have logged in or and those who haven’t. An example is on the new SAArchitect site when you are logged in it should let you change your password and if you aren’t logged in then it should let you apply or request a forgotten password.
So putting my developer cap on (or at least adjusting it since it doesn’t ever come off) I fired up my trusty copy of Visual Studio. I needed VS as I had decided to solve this using ASP.NET and a web part which does come with WSS, the Content Editor Web Part (CEWP). Utilizing all of the power of Visual Studio 2008, I toiled away to produce my ASP.NET page with a staggering 22 lines of code which looks something like this:
Note: All the code is available in the file at the end of this post.
1: <%@ Page Language="C#" ContentType="text/xml" %>
2:
3: <%@ Import Namespace="System" %>
4: <%@ Import Namespace="System.Globalization" %>
5: <%@ Import Namespace="System.Web.UI" %>
6: <script language="C#" runat="server">
7: protected override void OnPreRender(EventArgs e)
8: {
9: string result = string.Empty;
10: if (Page.User.Identity.IsAuthenticated)
11: {
12: result = String.Format(CultureInfo.CurrentCulture, "<?xml version=\"1.0\" encoding=\"utf-8\" ?>" +
13: "<user xmlns=\"http://schemas.saarchitect.net/ajax/2008/09/user\" username=\"{0}\" />", Page.User.Identity.Name);
14: }
15: else
16: {
17: result = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>" +
18: "<user xmlns=\"http://schemas.saarchitect.net/ajax/2008/09/user\" username=\"\" />";
19: }
20: Response.Write(result);
21: }
22: </script>
For those out there looking at that code and thinking it looks a little odd, it could be that the code all goes in the .aspx page itself. No code behind magic or web.configs or app_data folders to weigh this down. At 22 lines of code it’s all very simple: just checking if you are authenticated and if you are it returns an XML fragment with your name in it, and if you aren’t a XML fragment with no name and even a pretty namespace. In reality that could have been smaller like <u a=”0”/> if you aren’t logged in and <u a=”1”/> if you are, but that isn’t very human readable ;) That single file sits on the WSS site in a document library, which is interesting (at least to me) because SharePoint will not let the code run by default as a way of protecting you from security issues. However if you are smart/brave/stupid enough you can tell SharePoint to let you run it, using the SharePoint web.config. Microsoft has a great article on how to do that over there.
Now that I have the code to tell me if I am logged in or not, I need to hide/show content based on it, which is easily done using the source editing options of the CEWP to plop in a bit of JavaScript. This bit of JavaScript uses a XMLHttpRequest to call the ASP.NET page and gets the result, which I check and based on the result show the relevant content as described below:
1: <script type="text/javascript">
2: //Partially from http://www.w3schools.com/XML/xml_http.asp
3: // Partially from http://en.wikipedia.org/wiki/Xmlhttprequest
4: // Provide the XMLHttpRequest class for IE 5.x-6.x:
5: if( typeof XMLHttpRequest == "undefined" ) XMLHttpRequest = function() {
6: try { return new ActiveXObject("Msxml2.XMLHTTP.6.0") } catch(e) {}
7: try { return new ActiveXObject("Msxml2.XMLHTTP.3.0") } catch(e) {}
8: try { return new ActiveXObject("Msxml2.XMLHTTP") } catch(e) {}
9: try { return new ActiveXObject("Microsoft.XMLHTTP") } catch(e) {}
10: throw new Error( "This browser does not support XMLHttpRequest." )
11: };
12:
13:
14: var xmlhttp;
15: function loadXMLDoc(url)
16: {
17: xmlhttp = new XMLHttpRequest();
18:
19: if (xmlhttp != null)
20: {
21: xmlhttp.onreadystatechange=state_Change;
22: xmlhttp.open("GET",url,true);
23: xmlhttp.send(null);
24: }
25: else
26: {
27: alert("Your browser does not support XMLHTTP.");
28: }
29: }
30:
31: function state_Change()
32: {
33: if (xmlhttp.readyState == 4)
34: {// 4 = "loaded"
35: if (xmlhttp.status == 200)
36: {// 200 = OK
37: var username = xmlhttp.responseXML.selectSingleNode('//user').getAttribute('username');
38: if (username.length > 0)
39: {
40: // user logged in
41: document.getElementById('resultText').outerHTML = '<P><A href="/memberPages/changepassword.aspx">Change Password</A></P>';
42: }
43: else
44: {
45: // anonymous
46: document.getElementById('resultText').outerHTML = '<P><A href="/Pages/signup.aspx">Signup</A><BR><A href="/Pages/forgotpassword.aspx">Lost Password</A></P>';
47: }
48: }
49: else
50: {
51: alert("Problem retrieving XML data");
52: }
53: }
54: }
55:
56: loadXMLDoc("/Pages/loggedinuser.aspx");
57: </script>
58: <span id="resultText"/>
59:
Admittedly this is not a solution that the little old lady with the white lunch box will be able to implement while she updates the bridge league site, but this might work just fine for a site about architecture which has a few smart people, a couple of MVP’s and me running around behind it.
You can download the page and the JavaScript in this file: DOWNLOAD
IMPORTANT NOTE: I have posted a follow up article which fixes some issues with this version. For more information see WSS and audience targeting - Part II.