HOW to create login account that shows error? if I create a program that shows username and password(if the user types a wrong

Question

this is my qn

Answer 1

For small controls like the length of characters, you can use HTML5 API, you can also use the RegExp for improve your searching. In addition, Javascript and HTML5 API can work together.

For professional controls like the searching of credentials in a database, learn PHP and MySql, Sololearn provides both.