Proxies are responsible for loading and saving the data in Ext JS. They are used by
Stores and they can also be used directly in a Model.
In Ext JS 3, we used to load and save data only in a server. Ext JS 4 introduces three new proxies, which can be used to store data locally, at the client side (browser).
Basically, in Ext JS 4, we have two types of proxies—client proxies and server proxies. The client proxies are: LocalStorageProxy, SessionStorageProxy, and MemoryProxy. The server proxies are: AjaxProxy, ScriptTagProxy, DirectProxy, and RestProxy.
In the following diagram, you can see the structure of how proxies are organized in Ext JS 4. We will look at each proxy closely in this topic:
Client proxies are used for ...