Open Save As Dialog From The Javascript

I need to realize the following scenario: I have a html page, where is a button and some textboxes. When I click the button i want to create an xml from the textboxes data and send

Solution 1:

From the answers and comments I have made a decision to use classic form submit. I will submit all form to the server and the xml will be constructed on the server side. Some of suggested solutions looks very good, but there are some restrictions in my target production environment. E.g. there is not possible to install any external components (e.g. flash.). the solution must work also in the older IE 8 browser (i cannot use all new HTML 5 features => i cannot use jsfiddle ). And it seems, that classic javascript doesn't support save as dialog especially from the security reasons.