Link of Brothers PHP training teaches you 20 points to improve efficiency

Use single quotes instead of double quotes to enclose strings, which is faster. Because PHP will look for variables in a string surrounded by double quotes, but not single quotes, note: only echo can do this, it is a "function" that can take multiple strings as parameters (Annotation: www. The lampbrother.net

PHP manual says that

echo
is a language construct, not a real function, so the function is enclosed in double quotes).



1. If the method of a class can be defined as static, try to define it as static, and its speed will be increased by nearly 4 times.



2. $row['id'] is 7 times faster than $row[id].



3. echo is faster than print, and uses multiple parameters of echo instead of string concatenation, such as echo $str1, $str2.



4. Determine the maximum number of loops before executing the for loop. Do not calculate the maximum value every time you loop. It is best to use foreach instead.



5. Unregister unused variables, especially large arrays, to free up memory.



6. Try to avoid using __get, __set, __autoload.



7. require_once() is expensive.



8. Try to use absolute paths when including files, because it avoids the speed of PHP looking for files in include_path, and it takes less time to parse the operating system path.



9. If you want to know the moment when the script starts to execute (Annotation: That is, the server receives the client request), it is better to use $_SERVER['REQUEST_TIME'] than time().



10. Functions replace regular expressions to accomplish the same function.



11. The str_replace function is faster than the preg_replace function, but the strtr function is four times more efficient than the str_replace function.



12. If a string replacement function accepts arrays or characters as parameters, and the length of the parameters is not too long, you can consider writing an additional replacement code, so that each pass parameter is a character, instead of just writing a line of code to accept the array as query and replacement parameters.



13. It is better to use an alternative branch statement (Annotation: that is, switch case) than to use multiple if and else if statements.



14. The practice of masking error messages with @ is very inefficient, extremely inefficient.



15. Open the mod_deflate module of apache to improve the browsing speed of web pages.



16. The database connection should be turned off when it is used up, and do not use long connections.



17. Error messages are expensive.



18. Incrementing local variables in a method is the fastest. Almost as fast as calling a local variable in a function.



19. Incrementing a global variable is 2 times slower than incrementing a local variable.



20. Incrementing an object property (eg: $this->prop++) is 3 times slower than incrementing a local variable.