This is a common question lately. First, I strongly recommend you consider purchasing an addon that does this for you. Build vs. buy is always touchy because sometimes it is easier just to write it than to get approval to purchase an addon. However, building an editable grid can be time consuming, depending on the complexity of your scenario and how reusable you want your code. Furthermore, most people will go the “bang it out” vs. “build a robust reusable solution” approach which typically means repetitive coding the next time you want an editable grid somewhere else in your CRM UI. We all know how that story goes…you were under the gun to get it built so you have copy/paste code everywhere. In the end, it is probably more cost effective to buy an addon. Here are the ones I know about:
If these options don’t work for you because you are forced to build instead of buy, then it starts off by understanding the CRM Web Services:
Use Web Service Data in Web Resources (REST and SOAP Endpoint) (fundamentals and when to use what)
You will need to review both subsections as well:
Use the REST Endpoint for Web Resources
Use the SOAP Endpoint for Web Resources
You need to understand both. Depending on a number of factors, you may use more of one vs. the other but will usually use some combination of both. For the SOAP service, I find the Silverlight CRM SOAP Library very useful.
Using Option Set Options with the REST Endpoint - JScript (Microsoft Dynamics CRM 2011)
Once you have been through all of this, you have the fundamentals necessary to build an editable grid.