SPServices is a great tool, really nice work, Marc Anderson (@sympmarc). It has been there all the time I have developed for SharePoint. But the fact that you work with XML and you must parse the attributes (!) was the reason why I prefered listdata.svc and Client Object Model, where you get objects in JSON or you have a nice API to get objects and their properties. But there is an area where SPServices are really the best tool: SharePoint Web Services which only understand SOAP like SocialDataService.asmx.

Sure you don’t want to load all the properties of listitems, like ContenTypeId and so on. We cannot avoid __metadata property :), but we can let listdata.svc to send only properties we want. By the way, the best tool for building listdata.svc queries is linqpad. Just write a usual Linq and linqpad converts it to web service url query:   Another great stuff is $count, just add ?$count and you get only the count of items, no other junk.

In one of my previous posts I showed how to retrieve data from listdata.svc with jQuery $.getJSON method. Getting data is very simple, listdata.svc provides a powerful restful interface with filtering, expanding and other features. Read the best and short introduction to listdata.svc by Suneet Sharma or a more detailed and technical article about filters, functions and operators by Mike Flasko at Microsoft with short examples here. Now back to listdata.svc in the SharePoint environment. Corey Roth provides a good images and sample results. For REST the “http verbs” are very important: GET, POST, PUT, DELETE.. SharePoint RESTful interface defines these verbs like that:

Javascript is very fast, responsive and unburdens the cpu at the server. Here I show a little example how to use jQuery.getJSON, jQuery.tmpl (wonderful plugin for rendering repeating data, repo hosted on Github) and REST-based service listdata.svc from /_layouts/_vti_bin/ folder. For this example I created a generic list “Contacts”, added two text fields Name and Phone. Add some phone numbers and try to go to /_vti_bin/ListData.svc/Contacts If you get 404-error, install a ADO.NET Data Services v1.5 CTP2, as described at dotnetmafia. If you want to know more about how to sort and filter, skip and limit results, read more at nothingbutsharepoint. If you encounter problems, follow Michaël’s blog post and download and install Windows6.1-KB976127-v6-x64.msu (if you have Windows Server 2008 R2), or NDP35SP1-KB976126-v2-x64.exe (if you have Windows Server 2008). After installing the version of the System.Data.Services.dll file is 3.5.30729.5004 (Windows Server 2008 R2), and 3.5.30729.4466 (Windows Server 2008). Allright, the remainder is pure javascript. In order to get it working you have to run the script from the same domain, meaning you can’t run javascript to retrieve the data from a html-file from your home folder. Create a webpart and add it to your page.