If you cannot use JS, then you will have to regenerate the page every time a change in one the menus is made by the user.

The http-protocol being essentially stateless, means that you will have to jump through a lot of hoops to "remember" what the previous state of the page was. Session-management springs to mind in that respect, but you can also keep the previous values of the menu-choices in some hidden fields.

Using hidden fields, it is easy to check which choices have changed and regenerate the page.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In reply to Re: CGI: which field has changed? by CountZero
in thread CGI: which field has changed? by davies

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