Simple Ajax
This example is similar to the first one, but it calls 4D for each entered value in the background. It simulates an order system. The user enters the article code, the system searches for product name (and price, etc) as soon the user leaves the field.
Each entered article code is sent to 4D, 4D answers with the same value plus a time stamp.
This example shows the browser cache problem, as soon a request was once send in a session, future requests for the same order code are not send again but answered from the browser cache. If the returned answer from the server will be unchanged (like product name), this can be seen as feature to avoid server traffic. If the answer is likely to be different (maybe amount of products in stock), we will see it as problem...