thanks for your answers.
the actual issue was, since i am assigning document action to print related controller methods, which i was not doing in SaveDetails() method.
document.formCreateDetails.action="CreateDetails/ExportLandscape";
or
document.formCreateDetails.action="CreateDetails/ExportPortrait";
I re-wrote my code as shown below for save event and it worked.
function SaveDetails()
{
....
if()
{
document.formCreateDetails.action="CreateDetails/Index";
return true
}
}
Thanks for all your answers, I really appreciate it. Happy coding....