PHP Learning Summary (i)

"PHP Object-oriented

5. If the current file has a namespace (namespace) when the PDO class is instantiated, the output will cause an error if the PDO class does not exist in the directory, so a backslash must be added before the PDO: \pdo
6. instantiating a class can also be stored without variables, such as: New PDO ()
7. preg_match ($pattern, $string); Returns the number of matches, parameter one is the regular expression, the second is the match content, this function matches only once, matches all please with Preg_match_all
8. preg_ Replace ('/\{\$ ([\w]+) \}/', ' B ', ' {$dd}f imitation {$dd}4s65f '); Replace the regular match to the content and return, parameter one is the expression, the second is the replacement content, the third is the original text
9. json_encode (); function Chinese garbled (u265/similar case ) and part of the symbol are converted by the workaround:

foreach ($data as $key = + $value) {$data [$key] = UrlEncode ($value);}

1. UrlEncode for each value, return to UrlDecode (Json_encode ())!
2. Namespace (namespace) used: A file app\ctrl\model.php, whose namespace should be namespace App\ctrl;
3. Spec: namespace per-level initial capitalization, class name capitalization, constant all caps
4. "Namespace and use keyword
5. Start a namespace for the class: namespace plugin;
6. Access this class with use: Using Plugin\nos;
7. Note: This class must be introduced (include) when using use to access the class
8. It is recommended to use Spl_autoload_register () to automatically load non-existent classes for you

"PHP Template

1. Why should I use a template?

• To separate PHP and HTML code, make maintainability even higher!

2. Why should I cache a template?

• To increase loading speed, improve performance and database endurance!

3. Why do I need to compile the template into a php file?

• The template uses some custom syntax, such as {$name}, in order to make it normal to display, you need to convert it to <?php echo $name output, the converted file compiled into a file, the next call directly!

4. How do I cache a template?

• Put the introduced compilation file as buffer Ob_start () and then use Ob_get_contents () to save the copied content to the cache file with File_put_contents ()

PHP Learning Summary (i)