As a newbie, the index username is not defined. Please solve it. Thank you.

Question

Undefined index: Thank you, brother, thank you

Answer 1

Also note that variable names should be standardized and $data should not be written as $date

Answer 2

Login.php determines that admin is not empty. Change the writing method. If you write it according to the teacher's writing method, it will get stuck.

Answer 3

Confirm the front-end request parameters, whether there is username