Multi-level linkage drop-down box to dynamically obtain the next level

Multi-level linkage drop-down box to dynamically obtain the next level. each level of data is XML and can support unlimited levels (the browser needs Microsoft. XMLDOM support) project requirements: a material category table, level 3, with a total of more than 7000 records.

Multi-level linkage drop-down box to dynamically obtain the next level. each level of data is XML and can support unlimited levels (the browser needs Microsoft. XMLDOM support)

Project requirements: a table of material categories, Level 3, with a total of more than 7000 records. if a table is obtained at a time, it will be very slow. Therefore, it uses dynamic reading, the cache is used on the server, and the efficiency is good.

The HTML code is as follows:

 

ChildSelectName indicates the name of the next Select

One of the xml is as follows: