User Registration function: Enter the verification code and click Gouges, automatically check the input verification code is correct. If correct, a green checkmark appears after the Captcha box

User Registration function: Enter the verification code and click Gouges, automatically check the input verification code is correct. If correct, a green checkmark appears after the Captcha box.
To achieve this function, what is the idea of seeking the guidance of the Great God

Reply to discussion (solution)

The onblur event occurs when the object loses focus.
The user loses focus and uses AJAX authentication, and the foreground is displayed based on the returned data.

After losing focus, Ajax submits the verification code to the backend check and returns the result.

example, generate Verification Code section will not do, the default generated verification code is 1234
Now enter the verification code in the box, then click Blank to see the results.

   
 
           
Verification Code:

server.php

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