Remember several basic PHP knowledge points in 20 seconds and basic PHP knowledge in 20 seconds.

Remember several basic PHP knowledge points in 20 seconds and basic PHP knowledge in 20 seconds.

Array:
Index Array: the Key of the array is an integer array, starting from 0.
Join array: the Key of the array is an array of strings.

// Index array $ arr = array ('I', 'love', 'you'); // associate the array $ arr0 = array ('apple' => "apple ", 'yellow' => "yellow ");

Foreach traversal Array

// Array traversal $ arr = array ("apple", "yellow"); foreach ($ arr as $ key = >$ value) {echo '<br> the key is: '. $ key. 'corresponding value :'. $ value ;}$ arr0 = array ('apple' => "apple", 'yellow' => "yellow"); foreach ($ arr0 as $ key =>$ value) {echo '<br> key :'. $ key. ', the corresponding value is :'. $ value ;}

Determine whether a function exists: function_exsits (function name)

Function sayHello () {echo 'hello';} $ test = 'sayhel'; if (function_exsits ($ test) {sayHello ();} // output hello

Constructor: method called when an object is created
Destructor: method called when an object is destroyed

Class Car () {public _ construct () {echo 'object created ';} public _ destruct () {echo 'object destroyed ';}} $ car = new Car ();

Strpos: String SEARCH method

$ Str = 'Hello world'; echo strpos ($ str, 'World'); // output 6, starting from 6th bits

Implode: Return Value: combines array elements into a string.

$ Arr = array ('abc', 'defg'); $ arr0 = implode ('', $ arr); print_r ($ arr0); // The result shows abcdefg.

Explode: Return value: the function returns an array composed of strings.

$ Str = "abc, defg"; $ arr = explode (',', $ str); print_r ($ arr); // The result returns an array with two elements: abc and defg

Author: By: Luo Jian yuan http://blog.csdn.net/sunyuan_software