PHP serialize () and unserialize ()

PHP function serialize () and
Unserialize () Description and case. To convert serialized strings back to PhP
Can use unserialize (). Serialize () can process any type other than resource. Even serialize () contains
Point to its own referenced array. References in arrays/objects of serialize () will also be stored.

Serialize () returns a string that contains a byte stream that represents value and can be stored anywhere. This facilitates storing or passing PHP values without losing their types and structures.

To convert serialized strings back to PhP
Can use unserialize (). Serialize () can process any type other than resource. Even serialize () contains
Point to its own referenced array. References in arrays/objects of serialize () will also be stored.

When an object is serialized, PHP tries to call the member function _ sleep () of the object before the sequential action (). This allows objects to be cleared before being serialized. Similarly, when you useUnserialize ()When the object is restored, the _ wakeup () member function is called.

Note: in PHP 3, object attributes will be serialized, but methods will be lost. PHP 4 breaks this restriction and can store attributes and methods at the same time. For more information, see the serialization object section of the class and object.

Serialize () and unserialize () are described in the PHP manual as follows:

Serialize-generates a storable representation of a value

Serialize-generate a representation of a stored value

Unserialize-creates a PHP value from a stored Representation

Unserialize-Create a PHP value from a stored Representation

Serialize, Translated as "serialization, continuous", usually called"Serialization"

This function is useful, especially when used with unserialize.

I think it is useful to store data in a database or record it in a file.

Of course, this type of data must be complex (neither complicated nor serialize is required, and I think at least it must be an array) and be non-"index or primary key" in the database ", of course, it is best
Database fields in the system and any searchProgramOf course, the data after serialize can still be searched, because the specific data is not encrypted or changed.

<? PHP
// Simple
$ Array = array ();
$ Array ['key'] = 'website ';
$ Array ['value'] = 'www .isoji.org ';
$ A = serialize ($ array );
Echo $;
Unset ($ array );
$ A = unserialize ($ );
Print_r ($ );

// Declare a class
Class dog {

VaR $ name;
VaR $ age;
VaR $ owner;

Function dog ($ in_name = "unnamed", $ in_age = "0", $ in_owner = "unknown "){
$ This-> name = $ in_name;
$ This-> age = $ in_age;
$ This-> owner = $ in_owner;
}

Function getage (){
Return ($ this-> age * 365 );
}

Function getowner (){
Return ($ this-> owner );
}

Function getname (){
Return ($ this-> name );
}
}
// Instantiate this class
$ Ourfirstdog = new dog ("Rover", 12, "Lisa and Graham ");
// Use the serialize function to convert this instance into a serialized string
$ Dogdisc = serialize ($ ourfirstdog );
Print $ dogdisc; // $ ourfirstdog has been serialized as a string O: 3: "dog": 3: {s: 4: "name"; s: 5: "Rover "; s: 3: "Age"; I: 12; S: 5: "owner"; s: 15: "Lisa and Graham ";}

Print '<br> ';

/*
Bytes -----------------------------------------------------------------------------------------
Here you can store the string $ dogdisc anywhere, such as Session, Cookie, database, and PHP files.
Bytes -----------------------------------------------------------------------------------------
*/

// Cancel this class here
Unset ($ ourfirstdog );

/* Restore operation */

/*
Bytes -----------------------------------------------------------------------------------------
Here, you can read the string $ dogdisc from your storage location, such as Session, Cookie, database, and PHP files.
Bytes -----------------------------------------------------------------------------------------
*/

// Here we use unserialize () to restore serialized objects.
$ PET = unserialize ($ dogdisc); // $ PET is the previous $ ourfirstdog object.
// Get the age and name attributes
$ Old = $ pet-> getage ();
$ Name = $ pet-> getname ();
// This class can be used without instantiation at this time, and both attributes and values remain in the state before serialization.
Print "our first dog is called $ name and is $ old days old <br> ";
Print '<br> ';
?>