Add a dynamic menu using Javascript

When registering information, you often need to use the drop-down menu to allow users to choose from, and you want to make the selection in the first drop-down box, affecting the content of the second drop-down box. Sometimes, if no selection is made in the first drop-down box, the second drop-down box will not be displayed on the page at all. To present a... SyntaxHighlighter. all ();

When registering information, you often need to use the drop-down menu to allow users to choose from, and you want to make the selection in the first drop-down box, affecting the content of the second drop-down box. Sometimes, if no selection is made in the first drop-down box, the second drop-down box will not be displayed on the page at all, in order to present a clearer page to the user.

 
Let's take a look at the effect:

 

 

Html source code:
[Html]
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6.Dynamic menu change 
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