类函数,=>,->,::,self,$this用法

//比较最大数值
class Math{
    public static function Max($num1, $num2){
        return $num1 > $num2 ? $num1 : $num2;
    }
}
    $a = 1000;     
    $b = 5000;     
    echo "显示 $a 和 $b 中的最大值是";
    echo Math::Max($a, $b); //返回5000

    echo '<hr>';
    
//类函数,=>,->,::,self,$this用法
class User{
    var $userData = array(
        'name'    => 'zhou_ein',
        'gender'  => '男',
        'age'     => 18,
    );
    public static $Data = array(
        'name'    => 'zhouEin',
        'gender'  => '男',
        'age'     => 16,
    );
    public $name  = '钢锅';
    public static $gender = '男';
	var $age = 20;
		//类函数private外部不能访问
	private static $address = 'XX路XX号';
       //类函数public外部可以访问
	public static function getData($input2=''){
        global $input1;
		if($input1){
			$data[] = $input1;
		}
		if($input2){
			$data[] = $input2;
		}
        $data[] = self :: $address;
		$data[] = $this -> name;
        $data[] = self :: $gender;
        $data[] = $this -> age;
        $data[] = $this -> userData;
        $data[] = self :: $Data;
        return $data;
    }
}
    $input1 = 'global外部变量';
	$input2 = '传参外部变量';
	
	echo User :: $gender;  //返回男  直接调用
	
	$data = new User;
    echo $data -> name;   //钢锅
    echo $data -> age;    //20

    var_dump($data -> getData($input2));  //返回所有数组和变量