PHP Lesson 1: Understanding PHP

Objective planning: through the first lesson, we can understand the php environment. 1. environment Awareness: 2. access Method: 3. modify the code and view it. 4. use of variables 5. code indentation must have a hierarchical relationship, and it is best to keep blank lines between codes. 6. variable name: 7. variable output: 8. three methods of variable: 1. environment Awareness: Software: download

Objective planning: through the first lesson, we can understand the php environment. 1. environment Awareness: 2. access Method: 3. modify the code and view it. 4. use of variables 5. code indentation must have a hierarchical relationship, and it is best to keep blank lines between codes. 6. variable name: 7. variable output: 8. three methods of variable: 1. environment Awareness: Software: http: // download

Target Planning:
Through the first lesson, we can understand the php environment.

1. Environment Awareness:
2. access method:
3. Modify and view the code.
4. Use of Variables
5. Code indentation must have a hierarchical relationship, and it is best to keep blank lines between codes.
6. variable naming:
7. Output of variables:
8. Three Methods of variables:

1. Environment Awareness:

Software: http://download.csdn.net/detail/junzaivip/7697331

The installation tutorial is very simple. You can click here on your own

Directory structure after installation:

2. access method:

Enter localhost in the browser to access

3. Modify and view the code.

We can modify index. php In the www directory above.

Php output html code:

  ";echo "Hello world";echo "/html";?>
Recommended syntax

 
  


4. Use of Variables
  


5. Code indentation must have a hierarchical relationship, and it is best to keep blank lines between codes.

6. variable naming:
. Try not to use Chinese Characters
. Try not to start with a number
. Try not to use meaningless letters
. Variable names are case-sensitive. function names are case-insensitive and class names cannot be case-sensitive.
6. 5. The variable definition must be added with $

7. Output of variables:
Echo $ name;


8. Three Methods of variables:
Echo ($ name); // output variable
Var_dump ($ name); // output array, and print type and length
Print_r ($ name); // output Array


Example:

  

Shown below

Through the above display, we can see that the display is very unattractive and does not need to be read, so the formatting output scheme is as follows:
  "; Print_r ($ arr); echo"
";?>

The result is as follows:

TIPS:

Utf-8 encoding, a Chinese character is 3 Characters

Gbk encoding, a Chinese character is 2 Characters