Easy to see a "now use XML data island to achieve multi-level related drop selection box"
The idea is actually unwinding to me a few days ago. But I think my method is simpler, and I don't need to call XML DOM. Data downloads are also small.
At that time, it was considered that there would be a lot of options, and the data structure defined to associate relationships should be efficient, too many downloads will enable the user.
At the same time, these definitions need to be dynamically generated on the server side, as well as the current definition method, as long as the nested cycle output is very easy to implement.
Further, it is versatility, flexibility. It is similar to what mentioned earlier.
JavaScript needs to display correctly
