composer

安装composer，在Linux上。

curl -sS https://getcomposer.org/installer | phpmv composer.phar /usr/local/bin/composer

第二步：安装完成之后输入

# composer -v

显示如下说明成功。

Do not run Composer as root/super user! See https://getcomposer.org/root for details   ______  / ____/___  ____ ___  ____  ____  ________  _____ / /   / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___// /___/ /_/ / / / / / / /_/ / /_/ (__  )  __/ /\____/\____/_/ /_/ /_/ .___/\____/____/\___/_/                    /_/Composer version 1.5.2 2017-09-11 16:59:25Usage:  command [options] [arguments]Options:  -h, --help                     Display this help message  -q, --quiet                    Do not output any message  -V, --version                  Display this application version      --ansi                     Force ANSI output      --no-ansi                  Disable ANSI output  -n, --no-interaction           Do not ask any interactive question      --profile                  Display timing and memory usage information      --no-plugins               Whether to disable plugins.  -d, --working-dir=WORKING-DIR  If specified, use the given directory as working directory.  -v|vv|vvv, --verbose           Increase the verbosity of messages: 1 for normal output, 2 for more verbose output and 3 for debug

第二步：接下来进入项目目录

初始化composer

composer init出现：Do not run Composer as root/super user! See https://getcomposer.org/root for details                                              Welcome to the Composer config generator                                              This command will guide you through creating your composer.json configPackage name (<vendor>/<name>) [root/test]: 输入名字Description []: 输入描述Author [, n to skip]:作者信息Minimum Stability []: stable  资源包的最低稳定版本，默认为 stablePackage Type (e.g. library, project, metapackage, composer-plugin) []: 选择你的类型：库、项目。一般用projectLicense []: 协议 MITWould you like to define your dependencies (require) interactively [yes]? noWould you like to define your dev dependencies (require-dev) interactively [yes]? no{    "name": "mly/test",    "description": "a test",    "type": "project",    "license": "MIT",    "authors": [        {            "name": "mly",            "email": "[e-mail]"        }    ],    "minimum-stability": "stable",    "require": {}}Do you confirm generation [yes]?生成上面的文件？ yes在目录下就生成了composer.json文件

切换到中国镜像，外国网站太慢

composer config repo.packagist composer https://packagist.phpcomposer.com  在composer.json所在目录下执行

接下来

composer install

在当前目录下生成了一个文件夹vendor

vendor目录结构：vendor----autoload.php          ----composer     ----autoload_classmap.php                                  ----autoload_namespaces.php                                  ----autoload_psr4.php(自动加载)                                  ----autoload_real.php                                  ----autoload_static.php                                  ----ClassLoader.php                                  ----installed.json                                  ----LICENSE

第三：文件自动加载：例如thinkPHP的function.php的加载

回到项目目录，新建一个common目录，在common下创建function.php文件，随便写个方法。

<?phpfunction test($str){    return md5($str);}

然后到项目中，打开composer.json文件，添加红色部分，中括号里面就是要引入文件的路径，需要引入其他文件的时候在中括号中加“,”继续写上路径就可以，之后执行composer dump

{    "name": "mly/test",    "description": "a test",    "type": "project",    "license": "MIT",    "authors": [        {            "name": "mly",            "email": "[e-mail]"        }    ],    "minimum-stability": "stable",    "require": {},    "repositories": {        "packagist": {            "type": "composer",            "url": "https://packagist.phpcomposer.com"        }    }    "autoload":{        "files":["common/function.php"]    }}

然后在项目中需要的地方引入vendor下的autoload.php就可以使用。

自动加载类：

{    "name": "mly/test",    "description": "a test",    "type": "project",    "license": "MIT",    "authors": [        {            "name": "mly",            "email": "[e-mail]"        }    ],    "minimum-stability": "stable",    "require": {},    "repositories": {        "packagist": {            "type": "composer",            "url": "https://packagist.phpcomposer.com"        }    }    "autoload":{        "files":["common/function.php"]//文件的自动加载        "psr-4":{"类的命名空间要双斜杠（App\\Home\\）":"文件路径（相对于composer.json的）"}    }}

之后运行composer dump

用到的地方引入autoload.php 然后实例化类就可以了（实例化的时候要加上那个类的命名空间或者use那个命名空间）psr-4:类名要和文件名一样

如果要用其他的工具类或者别人写好的类或功能

访问：https://packagist.org/  可以在里面搜索，选择★高的或者下载量大的可能bug比较少，并且有使用文档。

在项目中运行 composer require +你查找到的类，完成之后到vendor目录下就会看到多了刚才下载的文件

然后在项目中引入autoload.php 实例化就可以用了