PHP方法链接

Question

任何人都可以解释为什么这段代码不起作用（内容$this->_string）是空的吗？

<?php 
class WordProcessor 
{ 
    public $_string = ''; 

    public function __constructor($text) 
    { 
     $this->_string = $text; 
    } 

    public function toLowerCase() 
    { 
     $this->_string = strtolower($this->_string); 
     return $this; 
    } 

    public function trimString() 
    { 
       echo $this->_string; 
     $this->_string = trim($this->_string); 
     return $this; 
    } 

    public function capitalizeFirstLetter() 
    { 
     $this->_string = trim($this->_string); 
     return $this; 
    } 

    public function printResult() 
    { 
     echo $this->_string; 
    } 
} 

$data = new WordProcessor("here Are some words! "); 
$data->trimString()->toLowerCase()->capitalizeFirstLetter()->printResult(); 

Answer 1

使用construct代替constructor？

Answer 2

其

public function __construct($text) 

不__constructor(..)