PHP类中的静态方法使用实例

    function __construct()
    {
        $this->num = 10;
    }

    function fun_1()
    {
        echo "I am a public method named fun_1.n";
        echo "The num of object is {$this->num}.n";
    }

    static function fun_2()
    {
        echo "I am a static method named fun_2.n";
    }

    function fun_3($n)
    {
        echo "The arg is {$n}n";
    }
}

$m = new MyClass;
$m->fun_1();
$m->fun_2();
$m->fun_3('test');

MyClass::fun_1();
MyClass::fun_2();
MyClass::fun_3('test');

输出结果：

lch@localhost:php $ php class_method.php
I am a public method named fun_1.
The num of object is 10.
I am a static method named fun_2.
The arg is test
I am a public method named fun_1.
PHP Fatal error:  Using $this when not in object context in /Users/lch/program/php/class_method.php on line 14

function __construct($pwd) {
  echo ‘Username:’,self::$username;   //输出静态属性
 
  self::$username = ‘admin’;  //为静态属性赋值
  $this->password = $pwd;   //为非静态属性赋值
}

public function show(){    //输出类属性
  echo ‘
Username:’,self::$username;
  echo ‘
Password:’,$this->password;
}

public static function sshow(){
  echo ‘
Username:’,self::$username;
  echo ‘
Password:’,$this->password;
}
}
user::$username = ‘root’;    //为赋值user类的静态属性赋值
$objUser = new user(’123456′);     //实例化user类
$objUser->sshow();
unset($objUser);
echo ‘
Username:’,user::$username;

/*
* 输出结果为：
* Username:root
* Username:admin
* Password:123456
* Usern
ame:admin
* */