从__constructor返回false(Return false from __constructor)

 你能否从构造函数返回false？ 
 
<?php


class ftp_stfp{

    //private vars of the class
    private $host;
    private $username;
    private $password;
    private $connection_type;
    private $connection = false;


    function __contruct( $host, $username, $password, $connection_type ){

        //setting the classes vars
        $this->host         = $host;
        $this->username     = $username;
        $this->password     = $password;
        $this->connection_type = $connection_type;

        //now set the connection into this classes connection
        $this->connection = $this->connect();

        //check the connection was set else return false
        if($this->connection === false){
            return false;   
        } 
    } ... etc etc the rest of the class
 
 致电课程： 
 
$ftp_sftp = new ftp_sftp( $host, $uname, $pword, $connection_type );
 
 这实际上是正确的，也就是说$ ftp_sftp var是false还是保持类取决于__construct方法的结果，还是这是完全错误的逻辑？ 

Can you return false from the contructor?
 
<?php


class ftp_stfp{

    //private vars of the class
    private $host;
    private $username;
    private $password;
    private $connection_type;
    private $connection = false;


    function __contruct( $host, $username, $password, $connection_type ){

        //setting the classes vars
        $this->host         = $host;
        $this->username     = $username;
        $this->password     = $password;
        $this->connection_type = $connection_type;

        //now set the connection into this classes connection
        $this->connection = $this->connect();

        //check the connection was set else return false
        if($this->connection === false){
            return false;   
        } 
    } ... etc etc the rest of the class
 
Call the class:
 
$ftp_sftp = new ftp_sftp( $host, $uname, $pword, $connection_type );
 
Is this actually correct, ie would the $ftp_sftp var either be false or hold the class depending on outcome of the __construct method, or is this completely wrong logic?

原文：https://stackoverflow.com/questions/14295761