PHP code reuse methods

To call files in scripts, PHP provides several main ways. The include() and require() functions are the most commonly used methods.
　1.Require() function

　When using require() to include an external file, as long as the php file is executed, the content of the external file will be included in the php file. When an error occurs in the included external file, the system will give An error message appears and the execution of the php file is stopped.
　Example:
　Program code for calling the file config.inc:
 　　　<?php echo "This is what is called: Hello! "; ?>
　Program code of the current script example01.php:
码 Echo "Code reuse examples:";
Require ('Config.inc'); // Call another file config.inc, output the content in config.inc







& & & GT ;
　The result is: Example of code reuse: This is what is called: Hello! Implemented using the require function.
　2.include() function
　When using include() to include an external file, the external file will only be included when the PHP file executes the include() function, and when an error occurs in the included external file, the system will only give a warning , the php file continues to execute downwards.
Example: 文 The program code of calling file Config2.inc:
& lt;? PHP Echo "Include function, very simple!";? & Gt; "Examples of code reuse 2:" ";
include ('config2.inc'); // Call another file config2.inc, output the content in config2.int
" & l & gt; ";
echo" Implemented by function. " ;
  ? ?>
　 The result is: Code reuse example 2: Use of include function, very simple! Implemented using include function.

　You can specify an explicit path by entering the full path or relative path of the file to be included.
　Example:
　include ('D: webpage mr sl 40.php' );
include (' .. sl 40.php ' ) ;

include ( ' 40.php' ) ; 🎜If no explicit path is specified, PHP Just look for included files in the current directory, and then look for the directories listed in the include_path setting in the php.ini file. 🎜