Question

在下面的代码中，我的输出中没有“处理”。我看到文件句柄是一个资源，文件被打开，调用FqReader的构造函数，我检查了所有这些。但是执行FqReader :: getread（）时，我看不到输出，返回的数组为空。当我把while（1）而不是现在的代码中的逻辑测试放在第一个while循环时也没有得到解释。

<?php

class FastqFile {
    function __construct($filename) {
        if (substr($filename, -3, 3) == '.gz') {
            $this->handle = gzopen($filename, 'r');
            return $this->handle;
        }
        else
            $this->handle = fopen($filename, 'r');
            return $this->handle;
    }
}

class FqReader {
    function __construct($file_handle) {
        $this->handle = $file_handle;
    }
    function getread() {
        while ($header = fgets($this->handle) !== false) {
            echo "handled";
            $bases = fgets($this->handle);
            $plus = fgets($this->handle);
            $scores = fgets($this->handle);
            yield array($header, $plus, $scores);
        }
    }
}

$filename = $argv[1];
$file_handle = new FastqFile($filename);
var_dump($file_handle);
$reader = new FqReader($file_handle);
var_dump($reader->getread());

输出：

object(FastqFile)#1 (1) {
  ["handle"]=>
  resource(5) of type (stream)
}
object(Generator)#3 (0) {
}

Answer 1

class Foo { public: Foo (int pInt) { .... } Foo (double pDouble) { .... } int i = 5; Foo foo(i); // explicit constructors Foo foo2(27); Foo foo3(2.9); Foo foo4 = i; // implicit constructors Foo foo5 = 27; Foo foo6 = 2.1;是$file_handle个实例。然后将该对象传递给FastqFile，但是您需要将该对象的句柄传递给fgets()。例如：

fgets()

使用class FqReader { function __construct($file_handle) { $this->handle = $file_handle->handle; } function getread() { while ($header = fgets($this->handle) !== false) { echo "handled"; $bases = fgets($this->handle); $plus = fgets($this->handle); $scores = fgets($this->handle); yield array($header, $plus, $scores); } } }并没有向您显示该错误。

Answer 2

确切地说，这就像一个魅力：

（使用函数打开文件，而不是类）

function openfq($filename)
{
    if (substr($filename, -3, 3) == '.gz') {
        $handle = gzopen($filename, 'r');
        return $handle;
    }
    else
        $handle = fopen($filename, 'r');
        return $handle;
}

class FqReader {
    function __construct($file_handle) {
        $this->handle = $file_handle;
    }
    function getread() {
        while (($header = fgets($this->handle)) !== false) {
            echo "handled";
            $bases = fgets($this->handle);
            $plus = fgets($this->handle);
            $scores = fgets($this->handle);
            yield array($header, $bases, $scores);
        }
    }
}

$filename = $argv[1];
$file_handle = openfq($filename);
var_dump($file_handle);
$reader = new FqReader($file_handle);
var_dump($reader->getread());
foreach($reader->getread() as $read) {
    var_dump($read);
}

生成器函数没有执行PHP

2 个答案: