Some uncommon features of PHP

1. variable function name. you can use a string to concatenate the function name functionaa ($ str) {echo $ str;} 1. variable function name. you can use a string to concatenate the function name.

Function aa ($ str ){
Echo $ str ;}$ function = "aa"; $ function ('Hello'); // ORcall_user_func ($ function, $ param );

2. list all functions and determine whether a function exists.

Get_defined_functions () function_exist ()

3. accept PUT requests, essential for PHP REST

Parse_str (file_get_contents ('php: // input'), $ put_vars );

4. parse time from string

Echo date ('Y-m-D', strtotime ('-1 month ago '));

5. View and call backtrace in DEBUG

$ Backtrace = debug_backtrace (); var_export ($ backtrace [0]) die ();

6. interactive command line, command line execution PHP

Php-a and php-r 'echo "hello ";'

For more information, see php-h.

7. memory usage detection

Memory_get_peak_usage () memory_get_usage ()