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1 indexed arrays

$fruit = Array ("Apple", "banana", "pineapple");

Print_r ($fruit);

There are three ways to initialize an indexed array:

1$arry[0] = "Apple";

2array (' 0 ' = "apple");

3array (' Apple '), the system starts from index 0 by default

4 Remove the value in the indexed array $fruit 0 = $fruit [' 0 '];

5for use, for use similar to C

Use of 5foreach

foreach ($fruit as $key = $value)

{

Echo ' first ' $key. ' The value is: '. $value;

}

2 Associative arrays

Associative array refers to an array of keys that are strings

$fruit = Array (' apple ' = ' apple ', ' orange ' = ' orange ')

Print_r ($fruit);

Creation of associative arrays

$arr = Array ();

$array [' apple '] = ' apple ';

Or

$arr = Array (' apple ' = ' apple ');

Take the value of the associative array $value = $fruit [' banana '];

foreach ($fruit as $key = $value)

Objects in 3PHP

1 Defining a class
Class Car {
var $name = ' car ';
function GetName () {
return $this->name;
}
}

$car = new car ();

$car->name = ' BMW ';

echo $car->getname ();

Variables in the same class have Public,private,protect

PHP uses __construct () to define a constructor in a class

Class Car {

function __construct ()

{

Print "constructor is called \ n";

}

function __destruct ()

{

The print "destructor is called \ n";

}

}

2 static properties and methods can be invoked without instantiating the class, directly using 类名::方法名 the method. Static properties do not allow an object to be called with an operator.

Static methods can also be dynamically called through variables

$func = ' getspeed ';

$classname = ' Car '

echo $className:: $func ();

Static methods cannot be called with this, and can be implemented with Self,parent Plus::

3 Overloading of methods

property is overloaded by using the __set,__get,__isset,_unset

ublic function __set ($key, $val) {        $this->ary[$key] = $val;    }        Public Function __get ($key) {        if (isset ($this->ary[$key]) {            return $this->ary[$key];        }        return null;    }

If the calling method does not exist, the __call method will be called, and if it is a static method, the __callstatic method will be called

Public Function __call ($name, $args) {        if ($name = = ' SpeedUp ') {            $this->speed + =;        }    }

4 advanced features for classes and objects

When all the properties of two instances of the same class are equal, you can use = = to determine

If the two variables of the same class are references to the same object, you can use = = = To determine

Object, copy an object with the keyword clone

Class Car {public    $name = ' car ';        Public Function __clone () {        $obj = new Car ();        $obj->name = $this->name;    }} $a = new car (), $a->name = ' new car '; $b = clone $a; var_dump ($b);

Object serialization, which can be serialized as a string by the Serialize method, used to store or pass data, and then deserialize the string into an object when needed by Unserialize.

$a = new Car (); $str = serialize ($a); The object is serialized into a string echo $str. ' <br> '; $b = Unserialize ($STR); Deserializes to Object Var_dump ($b);

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