我知道我在这方面非常晚，但我提出了一个相当灵活的模式，应该允许一些真正有趣和通用的实现。

像往常一样设置类，使用您喜欢的任何变量。

class MyClass{ protected $myVar1; protected $myVar2; public function __construct($obj = null){ if($obj){ foreach (((object)$obj) as $key => $value) { if(isset($value) && in_array($key, array_keys(get_object_vars($this)))){ $this->$key = $value; } } } } } When you make your object just pass an associative array with the keys of the array the same as the names of your vars, like so... $sample_variable = new MyClass([ 'myVar2'=>123, 'i_dont_want_this_one'=> 'This won\'t make it into the class' ]); print_r($sample_variable); The print_r($sample_variable); after this instantiation yields the following: MyClass Object ( [myVar1:protected] => [myVar2:protected] => 123 ) Because we've initialize $group to null in our __construct(...), it is also valid to pass nothing whatsoever into the constructor as well, like so... $sample_variable = new MyClass(); print_r($sample_variable); Now the output is exactly as expected: MyClass Object ( [myVar1:protected] => [myVar2:protected] => ) The reason I wrote this was so that I could directly pass the output of json_decode(...) to my constructor, and not worry about it too much. This was executed in PHP 7.1. Enjoy!

为了回应Kris的最佳答案(顺便说一句，他帮助我设计了自己的课程)，这里有一个修改过的版本，供那些可能会觉得有用的人使用。包括用于从任何列中进行选择和从数组中转储对象数据的方法。干杯!

public function __construct() {
    $this -> id = 0;
    //...
}

public static function Exists($id) {
    if (!$id) return false;
    $id = (int)$id;
    if ($id <= 0) return false;
    $mysqli = Mysql::Connect();
    if (mysqli_num_rows(mysqli_query($mysqli, "SELECT id FROM users WHERE id = " . $id)) == 1) return true;
    return false;
}

public static function FromId($id) {
    $u = new self();
    if (!$u -> FillFromColumn("id", $id)) return false;
    return $u;
}

public static function FromColumn($column, $value) {
    $u = new self();
    if (!$u -> FillFromColumn($column, $value)) return false;
    return $u;
}

public static function FromArray($row = array()) {
    if (!is_array($row) || $row == array()) return false;
    $u = new self();
    $u -> FillFromArray($row);
    return $u;
}

protected function FillFromColumn($column, $value) {
    $mysqli = Mysql::Connect();
    //Assuming we're only allowed to specified EXISTENT columns
    $result = mysqli_query($mysqli, "SELECT * FROM users WHERE " . $column . " = '" . $value . "'");
    $count = mysqli_num_rows($result);
    if ($count == 0) return false;
    $row = mysqli_fetch_assoc($result);
    $this -> FillFromArray($row);
}

protected function FillFromArray(array $row) {
    foreach($row as $i => $v) {
        if (isset($this -> $i)) {
            $this -> $i = $v;
        }
    }
}

public function ToArray() {
    $m = array();
    foreach ($this as $i => $v) {
        $m[$i] = $v;    
    }
    return $m;
}

public function Dump() {
    print_r("<PRE>");
    print_r($this -> ToArray());
    print_r("</PRE>");  
}

你可以这样做:

public function __construct($param)
{
    if(is_int($param)) {
         $this->id = $param;
    } elseif(is_object($param)) {
     // do something else
    }
 }

你可以像下面这样做，非常简单明了:

public function __construct()    
{
   $arguments = func_get_args(); 

   switch(sizeof(func_get_args()))      
   {
    case 0: //No arguments
        break; 
    case 1: //One argument
        $this->do_something($arguments[0]); 
        break;              
    case 2:  //Two arguments
        $this->do_something_else($arguments[0], $arguments[1]); 
        break;            
   }
}

正如这里已经展示的，在PHP中有许多方法来声明多个构造函数，但是没有一种方法是正确的(因为PHP技术上不允许这样做)。 但这并不能阻止我们破解这个功能…… 下面是另一个例子:

<?php

class myClass {
    public function __construct() {
        $get_arguments       = func_get_args();
        $number_of_arguments = func_num_args();

        if (method_exists($this, $method_name = '__construct'.$number_of_arguments)) {
            call_user_func_array(array($this, $method_name), $get_arguments);
        }
    }

    public function __construct1($argument1) {
        echo 'constructor with 1 parameter ' . $argument1 . "\n";
    }

    public function __construct2($argument1, $argument2) {
        echo 'constructor with 2 parameter ' . $argument1 . ' ' . $argument2 . "\n";
    }

    public function __construct3($argument1, $argument2, $argument3) {
        echo 'constructor with 3 parameter ' . $argument1 . ' ' . $argument2 . ' ' . $argument3 . "\n";
    }
}

$object1 = new myClass('BUET');
$object2 = new myClass('BUET', 'is');
$object3 = new myClass('BUET', 'is', 'Best.');

使用和理解多个构造函数的最简单方法:

希望这能有所帮助。：）

我知道我在这方面非常晚，但我提出了一个相当灵活的模式，应该允许一些真正有趣和通用的实现。

像往常一样设置类，使用您喜欢的任何变量。

class MyClass{ protected $myVar1; protected $myVar2; public function __construct($obj = null){ if($obj){ foreach (((object)$obj) as $key => $value) { if(isset($value) && in_array($key, array_keys(get_object_vars($this)))){ $this->$key = $value; } } } } } When you make your object just pass an associative array with the keys of the array the same as the names of your vars, like so... $sample_variable = new MyClass([ 'myVar2'=>123, 'i_dont_want_this_one'=> 'This won\'t make it into the class' ]); print_r($sample_variable); The print_r($sample_variable); after this instantiation yields the following: MyClass Object ( [myVar1:protected] => [myVar2:protected] => 123 ) Because we've initialize $group to null in our __construct(...), it is also valid to pass nothing whatsoever into the constructor as well, like so... $sample_variable = new MyClass(); print_r($sample_variable); Now the output is exactly as expected: MyClass Object ( [myVar1:protected] => [myVar2:protected] => ) The reason I wrote this was so that I could directly pass the output of json_decode(...) to my constructor, and not worry about it too much. This was executed in PHP 7.1. Enjoy!