How to use ajax to realize the cascade operation of drop-down menu

This article mainly introduces how to use ajax to realize the cascading operation of drop-down menu, which has certain reference value. Interested friends can refer to it. I hope you will gain a lot after reading this article. Let Xiaobian take you to understand it together.

In development, we often encounter cascading menu operations, such as: country, city, township selection, etc. When a country is selected, the menu at the back will list the cities in that country. When a city is selected, the menu at the back will list the corresponding towns.

There are two ways to solve this menu cascade operation, I understand:

① Use js to achieve, the cascade data used by the page into js, when the page is loaded, through js display to the corresponding select, there are many solutions to this method, the most intuitive one is to put into a multidimensional array, everyone's thinking is different, here will not explain in detail.

② Use Ajax asynchronous dynamic loading, and then display to the corresponding select, this method is very convenient, recommended to use in development.

Here's a small example in development:

JSP Short Page:

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