PHP设置可选参数

Question

class JSON_Response{
            private $ResponseCode = "RVN-775";
            private $ResponseDescription = "Unknown Request";
            private $ResponseOf = "Unknown";
            private $ResponsePayload = array("PayloadEmpty"->"Yes");

            function __construct(
                            $ResponseCode = null,
                            $ResponseDescription = null,
                            $ResponseOf = null,
                            $ResponsePayload = null,
                            )
        {
            $this->ResponseCode = $ResponseCode ? $ResponseCode : $this->ResponseCode;
            $this->ResponseDescription = $ResponseDescription ? $ResponseDescription : $this->ResponseDescription;
            $this->ResponseOf = $ResponseOf ? $ResponseOf : $this->ResponseOf;
            $this->ResponsePayload = $ResponsePayload ? $ResponsePayload : $this->ResponsePayload;

        }
    }

有什么更好的方法可以写吗？

我希望如果构造函数在创建对象时获取参数，则要设置类变量，如果没有给出参数，则我希望类变量为默认值。

Answer 1

如果传递了一些参数，这将覆盖默认值：

class JSON_Response{
      function __construct(
                        $ResponseCode = "RVN-775",
                        $ResponseDescription = "Unknown Request",
                        $ResponseOf = "Unknown",
                        $ResponsePayload =  array("PayloadEmpty"->"Yes"),
                        )
    {
        $this->ResponseCode = $ResponseCode;
        $this->ResponseDescription = $ResponseDescription;
        $this->ResponseOf = $ResponseOf;
        $this->ResponsePayload = $ResponsePayload;

    }
}

Answer 2

您可以尝试传递数组：

function __construct($args) { 
   foreach ($args as $k => $v) {
       //if (property_exists($this,$k)) -- optionally you want to set only defined properties
       $this->{$k} = $v;
   }
}

然后使用以下方法创建对象：

$object = new JSON_Response(array(
    'ResponseOf' => 'test'
));

Answer 3

如果params数组存在类变量键，则可以在数组中使用所有__constructor()并在类变量中分配值，这样可以减小代码大小，更好地使用它，请参见下面的示例代码

<?php

class JSON_Response {

    private $ResponseCode = "RVN-775";
    private $ResponseDescription = "Unknown Request";
    private $ResponseOf = "Unknown";
    private $ResponsePayload = array("PayloadEmpty" => "Yes");

    function __construct($params = array()) {
        if(!empty($params)){
            foreach ($params as $k => $v){
                $this->{$k} = $v;
            }
        }
    }
}

#call class from with array params
$class_params = array('ResponseCode' => '', 'ResponseDescription' => '',
 'ResponseOf' => '', 'ResponsePayload' => '');
$obj = new JSON_Response($class_params);

如果params键中不存在任何类变量，则将使用类变量默认值