>Hi,
>
>I am taking a night course on Javascript (had only two classes) in order to understand jQuery better, when start using it. But meanwhile I am trying to understand where jQuery would be helpful in an ASP.NET application. So I have a specific situation where I am thinking if jQuery would be applicable (if I knew it).
>
>On one of the pages of my ASP.NET application there are two drop-down lists, one for Sites and another for Buildings. User can select a site and the page is posted back to the server (on Sites drop-down change) and the list of buildings for selected site is built. So user will see Buildings per Site. The re-posting of the page is not a really big deal but I thought that maybe if I used jQuery I would eliminate the reposting of the page. That is, I could build the dataset/dataview of all building on initial posting of the page. And then via jQuery the building drop-down list would show only buildings of the selected site. My understanding is that since jQuery is a library of javascript functions reposting would not be necessary. Is such a thing doable with jQuery? TIA.

Yes. Similar example here: http://stackoverflow.com/questions/5748532/jquery-filter-list-box-based-on-the-combobox

But if the total number of buildings for all sites is large (and the user is only likely to inspect a small number of sites) then it may be more efficient to just pull the required data from the server for a selected site without round-tripping the entire page. In that case you could look at a ajax/json solution......