View source for AJAX calling an external webservice from the client

== Problem description from [[User:PERT| Per Thomson]] ==
I'm going to use an external [[WebService]] which check if an adress exist.

A year ago I tested using webservice a little so I shouldn't be quite unfamilar with that subject but . . . So far I have created a webservice client subclass from the [[WSDL]]. 

Now  I'm stuck about how to invoke the external webservice. 

The client/user type in a new address on a page that use the [[AJAX_Library_for_Visual_DataFlex]]    but the address has to be validated before a save may be performed.

== Solving it ==

In overall the easy way would be to call the external webservice on the serverside.  It is rather complex handling [[SOAP]] in javascript --[[User:Jka|Jka]] 15:03, 13 September 2007 (CEST)

I agree - handling it in the [[JavaScript]] is less than ideal, as this would be an example of [http://en.wikipedia.org/wiki/Cross-site_scripting cross site scripting] (in the sense that a script would be calling a site other than the one it was served from - OK in this context, but might be blocked by some security controls).  It will be a little slower, but in all probability this will not show up to the user.  [[User:Mikepeat|Mike]] 16:10, 22 November 2007 (CET)

== General knowledge ==
*[[Using the AJAX Library]]
*[[Using a WebService]]
*[[VDF Webservice Class]]


attaching a javascript function to onBeforeSave (inside initForm):

 oForm.onBeforeSave = function(oVdfForm, sTable){
        alert("onBeforeSave: " + oVdfForm + " " + sTable);
    }

[[Category:AJAX]]
[[Category:Web Services]]
[[Category:Challenges]]