发射箱喷口

Question

我在https://github.com/box/spout 下载了 Box / Spout，但我在启动 Spout 时遇到了问题。 我将文件复制到 WAMP 的文件夹中。

<?php 
use Box\Spout\Writer\WriterFactory;
use Box\Spout\Common\Type;

$writer = WriterFactory::create(Type::XLSX);
$writer->openToBrowser($fileName); // stream data directly to the browser
$writer->addRows($multipleRows); // add multiple rows at a time
$writer->close();
?>

我创建了 index.php 文件，Spout 文件位于 WWW/Spout/Box/Common、Reader 和 Writer 文件夹中。 我有这个错误：

( ! ) 致命错误：找不到类“Box\Spout\Writer\WriterFactory” C:\wamp\www\Spout\Index.php 在第 5 行

问题出在哪里？

Answer 1

下载文件是不够的。如果您不使用 Composer（这是使用 Spout 的推荐方式），则需要添加一个额外的自动加载器（它将为您自动加载类）。由于 Spout 符合 PSR4，因此自动加载其类并不难。

以下是一些可用于自动加载 Spout 类的工作代码：

Psr4Autoloader.php

<?php

namespace Autoloader;

class Psr4Autoloader
{
    /**
     * An associative array where the key is a namespace prefix and the value
     * is an array of base directories for classes in that namespace.
     *
     * @var array
     */
    protected $prefixes = array();

    /**
     * Register loader with SPL autoloader stack.
     * 
     * @return void
     */
    public function register()
    {
        spl_autoload_register(array($this, 'loadClass'));
    }

    /**
     * Adds a base directory for a namespace prefix.
     *
     * @param string $prefix The namespace prefix.
     * @param string $base_dir A base directory for class files in the
     * namespace.
     * @param bool $prepend If true, prepend the base directory to the stack
     * instead of appending it; this causes it to be searched first rather
     * than last.
     * @return void
     */
    public function addNamespace($prefix, $base_dir, $prepend = false)
    {
        // normalize namespace prefix
        $prefix = trim($prefix, '\\') . '\\';

        // normalize the base directory with a trailing separator
        $base_dir = rtrim($base_dir, DIRECTORY_SEPARATOR) . '/';

        // initialize the namespace prefix array
        if (isset($this->prefixes[$prefix]) === false) {
            $this->prefixes[$prefix] = array();
        }

        // retain the base directory for the namespace prefix
        if ($prepend) {
            array_unshift($this->prefixes[$prefix], $base_dir);
        } else {
            array_push($this->prefixes[$prefix], $base_dir);
        }
    }

    /**
     * Loads the class file for a given class name.
     *
     * @param string $class The fully-qualified class name.
     * @return mixed The mapped file name on success, or boolean false on
     * failure.
     */
    public function loadClass($class)
    {
        // the current namespace prefix
        $prefix = $class;

        // work backwards through the namespace names of the fully-qualified
        // class name to find a mapped file name
        while (false !== $pos = strrpos($prefix, '\\')) {

            // retain the trailing namespace separator in the prefix
            $prefix = substr($class, 0, $pos + 1);

            // the rest is the relative class name
            $relative_class = substr($class, $pos + 1);

            // try to load a mapped file for the prefix and relative class
            $mapped_file = $this->loadMappedFile($prefix, $relative_class);
            if ($mapped_file) {
                return $mapped_file;
            }

            // remove the trailing namespace separator for the next iteration
            // of strrpos()
            $prefix = rtrim($prefix, '\\');   
        }

        // never found a mapped file
        return false;
    }

    /**
     * Load the mapped file for a namespace prefix and relative class.
     * 
     * @param string $prefix The namespace prefix.
     * @param string $relative_class The relative class name.
     * @return mixed Boolean false if no mapped file can be loaded, or the
     * name of the mapped file that was loaded.
     */
    protected function loadMappedFile($prefix, $relative_class)
    {
        // are there any base directories for this namespace prefix?
        if (isset($this->prefixes[$prefix]) === false) {
            return false;
        }

        // look through base directories for this namespace prefix
        foreach ($this->prefixes[$prefix] as $base_dir) {

            // replace the namespace prefix with the base directory,
            // replace namespace separators with directory separators
            // in the relative class name, append with .php
            $file = $base_dir
                  . str_replace('\\', '/', $relative_class)
                  . '.php';

            // if the mapped file exists, require it
            if ($this->requireFile($file)) {
                // yes, we're done
                return $file;
            }
        }

        // never found it
        return false;
    }

    /**
     * If a file exists, require it from the file system.
     * 
     * @param string $file The file to require.
     * @return bool True if the file exists, false if not.
     */
    protected function requireFile($file)
    {
        if (file_exists($file)) {
            require $file;
            return true;
        }
        return false;
    }
}

autoload.php

<?php

require_once "Psr4Autoloader.php";

$loader = new \Autoloader\Psr4Autoloader;
$loader->register();
$loader->addNamespace('Box\Spout', 'vendor/box/spout/src/Spout');

将这两个文件添加到项目后，请确保 autoload.php 中的 require_once 路径正确，最后添加 require_once "path/to/autoload.php" 在您的根文件中（如 index.php）或您认为更合适的任何位置。