Why is there no error reported in var_dump($meiyou)?

Question

When I run my own code, I keep getting errors:

Notice: Undefined variable: meiyou in E:\work\study\PHP\phpstudy\www\127.0.0.2\phpstu_1.php on line 3

Then a NULL will be printed, but it is correct in the example. Why is this?

Answer 1

This is not an error. . Just a reminder that this variable is not declared. . . You can enter a piece of code in front to cancel the reminder

Answer 2

Looking at your error report, there is no $ in front of the variable name

Answer 3

Notice: Undefined variable: meiyou

The variable is undefined

Answer 4

The path is wrong