例如,假设我有以下内容：

class numbers{

    function __construct($number){
        $this->number = (int)$number;
    }

    function add($add){
        $this->added = $this->number + $add;
    }

    function multiply($multiply){
        $this->multiplied = $this->number * $multiply;
    }

    function minus($minus){
        $this->minused = $this->number - $minus;
    }

    function number(){
        return $this->number();
    }
}

现在让我们说我想应用add,然后乘以然后减去.每个阶段都可能失败(我没有在示例中包含它,但想象它就在那里).这是我的问题所在,我应该这样做：

$numbers = new numbers(8);
if($numbers->add(7)){
    if($numbers->multiply(6)){
        if($numbers->minus(7){
            echo $numbers->number();
        }else{
            echo 'error minusing';
        }   
    }else{
        echo 'error multiplying number';
    }   
}else{
    echo 'error adding number';
}

或者我应该在构造函数中包含该部分,例如：

class numbers{

    function __construct($number){
        $this->add(6);
        $this->multiply(9);
        $this->minus(7);
        if($this->error){
            return false;
        }else{
            return true;
        }
    }

    function add($add){
        $this->added = $this->number + $add;
        if(!this->added){
            $this->error = "couldn't be added";
        }
    }

    function multiply($multiply){
        $this->multiplied = $this->number * $multiply;
        if(!this->multiplied){
            $this->error = "couldn't be multiplied";
        }
    }

    function minus($minus){
        $this->minused = $this->number - $minus;
        if(!this->minused){
            $this->error = "couldn't be minused";
        }
    }

    function number(){
        return $this->number();
    }

    function error(){
        return $this->error();
    }

}

然后简单地做：

$numbers = new numbers(5);
if($numbers){
    echo $numbers->number();
}else{
    echo $numbers->error();
}

对不起,如果示例是长卷(也忽略错误,我在这里写它只是为了概述我正在尝试做的,这不是我正在使用的代码…)但我不知道如何短语没有例子的问题.基本上,我应该检查班级内部的错误,还是应该在我打电话给班级时在外面做？