Why is there no need to change pages?

During the past two days, I am busy and want to study Ajax-related technologies in depth for better development in the future. After all, I only use the updatepanel of Atlas, encapsulated Ajax server-side controls and other early-stage Ajax applications are not a long-term plan.
After reading the relevant documents and demos of prototype. js and script. aculo. Us, we have truly opened up our own horizons. In addition to asynchronous requests, Ajax also has the most important thing: how to update the returned data to the page. Currently, we use DOM objects to partially update the page and read the script. aculo. after the development kit of us, there is a feeling that the meaning of Ajax technology's "Asynchronous Update" is even weaker, or they do not exist for Ajax alone at all, to be more specific, they exist to develop a richer client experience. However, how to update the viewstate of a page, that is, how to make the page content updated by Ajax be refresh is a very tricky problem, for example, many Ajax frameworks now provide a page drag function, but once the page is refreshed, all the drag and drop modifications have just been made. How can we save these operations, how do I save them in viewstate? In other words, they are originally all client operations, and there is no viewstate concept at all, so it doesn't matter whether the status is retained.
Or is there a problem that I have been thinking about today, that is, refreshing new pages? Page operations cannot be refreshed without refreshing, but should pages be refreshed? Is it too much? Indeed, I keep thinking that Program The internal jump pages do not need to be refreshed, and they are too handsome. However, no reasonable method has been found. Why is there such an idea? I want to solve the problem that the navigation menu of the program is not refreshed. If the menu uses drag-and-drop, Auto Hide, auto contract, and other technologies (I don't know how Google pages are implemented, there is a dynamic display menu on the other side of the custom page, and its page can also be adaptive to the client resolution, in the 800*600 and 1024*768, even in any mode, the page can be displayed in full screen without any deformation or horizontal scroll bars .) If the page is switched, none of these operations will be lost. So I want to know how to skip the page without refreshing it. This worry can be eliminated. At present, the main ideas are as follows:
1. It is the simplest way to use the framework page, but it is the method that I do not want to use. It can be said that I would like to use the above functions, and I am not allowed to use this method to implement it.
2. A bold assumption: use only one dynamic page, write all other operations in the user control, and dynamically create these user controls based on the menu requirements for user operations. However, in this case, other problems may occur. At least the development difficulty will increase, right?
3. No, there are no more ideas at present. As there is no lack of relevant experience and knowledge, I cannot think of a better method for the moment.
I just want to have a deeper understanding.