Read php in detail. php essentials

After reading "Let's talk about php", the key points of php will be followed by the recent "Let's talk about php". In fact, all the key points of knowledge have been touched by the differences in the descriptions of the same knowledge in different books, achieving the purpose of understanding the same knowledge. I did not read the key points in the unit order. the key points are not all outline points, but I think they are very important in my work (but they are not very reliable) and need to be remembered. Some things have been used repeatedly, but I have not read php in detail.

I recently read php in detail. In fact, I have been familiar with all the key points of my knowledge. I have learned the differences in the descriptions of the same knowledge in different books, so that I can be considerate.
I did not read the key points in the unit order. the key points are not all outline points, but I think they are very important in my work (but they are not very reliable) and need to be remembered.

Some things are used over and over again, so I have not considered the details or principles too carefully;

Some knowledge has been repeatedly tested in php pen questions;

In short, this record will be helpful for future work!

Constantly update ....

 

Chapter 8 application of functions

1. the function calls external variables internally.
Global $ var;
$ GLOBALS [var];

2. Functions and definitions of static variables

The internal dynamic variables of the function are automatically released after the function call ends. if you want the internal variables to remain in the memory after the function is executed, use static variables.
Static variables are initialized only when the function is called for the first time during script execution.
Static $ var = 0;

3. recursive function definition
Be sure to understand and use it flexibly.
4. use the custom function library
The differences between include, require, include_once, and require_once must be understood.