1. Problems existing in traditional websites
- In the case of a slow network speed, the page takes a long time to load and users have to wait
- After the form is submitted, if one item fails, you need to fill in all the forms again
- A page is reloaded, wasting resources and increasing user waiting time
2. Summary of Ajax
Ajax is a set of methods provided by the browser to enable the page to update data without refreshing, improving the user experience of browsing web applications.
3. Application scenarios of Ajax
- More data is pulled and loaded on the page
- There is no refresh page for list data
- Form items leave focus data validation
- Search box prompts text drop – down list
4. Ajax runtime environment
Ajax techniques need to run in the web environment to work, and the current course uses the server created by Node as the web server.