action function without action method is a client or server action?

Question

I have written simple button to wash away the error using action function.

1. I clicked some wrong value, it gives an error using apex page message.
2. I selected right value now.
3. I call JavaScript function to call action function which will re-render the apex page message section.

Question above is:

I simple used action function to re-render the section. which doen't have any action method in it. Do you think its a server call or client calll ?

Answer 1

apex:actionFunction always calls the server, even if no action is specified. This allows the view state to be updated and components to be rendered according to new data (typically user input, but may also be from another source).

reRender causes specific elements to be updated. If you do not specify a reRender, then the page reloads. In either case, as before, the view state is updated and elements are rendered according to updated data.

This same general behavior occurs for all elements that have an action and reRender attribute, including apex:commandButton, apex:commandLink, apex:actionFunction, and apex:actionPoller.

Answer 2

actionfunction makes server side call when we use action which makes a call to controller method.

If an action is not specified, the page simply refreshes. Refer apex:actionFunction

re-render works on client side. Now you re-render a pageblocktable which is getting displayed based on list from server then definitely a server side call will be happening.