How to create a web service in javascript

[JoseSanchez]

Hi all

Is there any sample similar to the one in .Net

http://resources.esri.com/help/9.3/arcgisserver/adf/dotnet/developer/scenarios/develop_app_ws.htm

or

http://help.arcgis.com/en/sdk/10.0/serveradf_net/conceptualhelp/index.html#//0002000001s8000000

that explains how to create a web server to query GIS layers

Thanks