Windows下编写php扩展（三）利用php-cpp在window上快速开发PHP扩展

引言

在前一篇文章《Windows下编写php扩展（二）将linux下的php-cpp项目移植到windows》说明了将php-cpp移植到windows的过程。

已移植到windows的phpcpp项目的完整的vs2017解决方案可在此下载

接下来谈一谈用php-cpp开发php扩展的过程，本次的实验平台是win10 企业版，visual C++ 2017 社区版。

基本工作内容

开发php扩展的工作区基本内容如下：

phpcpp-devinclude 目录下存放要引用的头文件，在phpcpp项目的linux版下，phpcpp-devincludep目录下的头文件与编译phpcpp项目时include目录下的头文件是完一样的。但在windows下编译时，因为编译器的一些差异，所以对phpcpp-devinclude目录下的少量文件做了修改。

phpcpp-devlib 中存放 phpcpp.dll及引入库 phpcpp.lib 。在此项目中并不实际需要phpcpp.dll ,运行时，phpcpp.dll应该放在php安装目录，与php.exe在同一个目录中。前一篇文章中所谈的php-cpp的主要生成结果就是phpcpp.dll与phpcpp.lib。通过使用phpcpp.dll ,使得php扩展的开发工作得到了很大的简化。

本项目生成的扩展dll的位置是： x64ReleasemyPhpcppExt.dll。要在php中使用该扩展，应该将myPhpcppExt.dll复制到
php安装目录的ext目录中，并修改php.ini,加上相应的加载扩展的指令。

文件夹x64是vs2017自动生成的文件夹，删除后执行生成解决方案命令又会重新生成。

install_ext.php 是一个小脚本，用于在测试扩展功能时方便地将扩展dll复制到目标文件夹，避免手工复制。如果路径变更了，也应相应地修改install_ext.php中的目标路径。

main.cpp 是扩展项目的源文件，其中有一些示例函数

phpcpp.h是包含文件的总入口，为了适应windows环境，与linux版本相比，做了一点路径上的小改动。

示例代码

#include "phpcpp.h"

Php::Value my_plus(Php::Parameters &params)
{
	return params[0] + params[1] ;
}

void my_example()
{
	// the C++ equivalent of the echo() function
	Php::out << "example 1" << std::endl;

	// generate output without a newline, and ensure that it is flushed
	Php::out << "example 2n" << std::flush;

	// or call the flush() method
	Php::out << "example 3n";
	Php::out.flush();


	// just like all PHP functions, you can call the echo() function 
	// from C++ code as well
	Php::echo("Example 4n");
	Php::out.flush();

}

void  my_echo()
{
	// the C++ equivalent of the echo() function
	Php::out << "my_echo ,test6" << std::endl;
	Php::out.flush();

}

Php::Value native_bubblesort(Php::Parameters &params)
{
	
	// there is one input array, cast the PHP variable to a vector of ints
	std::vector<int> input = params[0];

	// loop through the array
	for (size_t i = 0; i < input.size(); i++)
	{
		// loop through the elements that were already processed
		for (size_t j = 1; j < input.size() - i; j++)
		{
			// move on if smaller
			if (input[j - 1] <= input[j]) continue;

			// swap elements
			int temp = input[j];
			input[j] = input[j - 1];
			input[j - 1] = temp;
		}
	}

	// done
	return input;
}

/**
 *  tell the compiler that the get_module is a pure C function
 */
extern "C" {
    
    /**
     *  Function that is called by PHP right after the PHP process
     *  has started, and that returns an address of an internal PHP
     *  strucure with all the details and features of your extension
     *
     *  @return void*   a pointer to an address that is understood by PHP
     */

    __declspec(dllexport) void *get_module()
    {
        // static(!) Php::Extension object that should stay in memory
        // for the entire duration of the process (that's why it's static)
        static Php::Extension extension("myPhpcppExt1", "1.0");
        
        // @todo    add your own functions, classes, namespaces to the extension
		//ÔÏîÄ¿ÖÐµÄadd·½·¨ÔÚÖØÔØÊ±ÓÐµãÎÊÌâ£¬ÏÖÔÚ½«Ìí¼Óº¯Êýµ½À©Õ¹µÄ¹¦ÄÜÖØÃüÃûÎª addFunc
		extension.add<my_plus>("my_plus", {
			Php::ByVal("a", Php::Type::Numeric),
			Php::ByVal("b", Php::Type::Numeric),
			});
		extension.add<my_example>("my_example");
		extension.add<my_echo>("my_echo");
		
		extension.add<native_bubblesort>("native_bubblesort",{	Php::ByVal("input", Php::Type::Array)	});
	
        // return the extension
        return extension;
    }
}

用于测试的php文件内容

<?php

$x=2;
$y = 4;
echo my_plus($x,$y);
echo "n";

my_example(1);

my_echo();


// fill an array with random numbers
$count = 10000;
$x = array();
for ($i=0; $i<$count; $i++) $x[] = rand(0, 1000000);

// run the native and scripted bubblesort functions
$start = microtime(true);
$y = native_bubblesort($x);
$native = microtime(true);
$x = scripted_bubblesort($x);
$scripted = microtime(true);

// show the results
echo("Native:   ".($native - $start)." secondsn");
echo("Scripted: ".($scripted - $native)." secondsn");
echo("rate:: ".($scripted - $native)/($native - $start)." secondsn");

//--------------------function-----------------------
function scripted_bubblesort(array $input)
{
    // number of elements in the array
    $count = count($input);
    
    // loop through the array
    for ($i = 0; $i < $count; $i++)
    {
        // loop through the elements that were already processed
        for ($j = 1; $j < $count - $i; $j++)
        {
            // move on if smaller
            if ($input[$j-1] <= $input[$j]) continue;
    
            // swap elements
            $temp = $input[$j];
            $input[$j] = $input[$j-1];
            $input[$j-1] = $temp;
        }
    }
    
    // done
    return $input;
}