如何安装?
官网地址：Composer (getcomposer.org)，目前个人看到的最新版为 2.4.4。
可以先尝试安装官方的介绍一步步操作：
Command-line installation
To quickly install Composer in the current directory, run the following script in your terminal. To automate the installation, use the guide on installing Composer programmatically.
注意：链接对应了类 Unix系统的安装手段。
php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"
unlink('composer-setup.php'); } echo PHP_EOL;"php -r "if (hash_file('sha384', 'composer-setup.php') === '55ce33d7678c5a611085589f1f3ddf8b3c52d662cd01d4ba75c0ee0459970c2200a51f492d557530c71c15d8dba01eae') { echo 'Installer verified'; } else { echo 'Installer corrupt'; php composer-setup.phpphp -r "unlink('composer-setup.php');"个人在笔记 [[【PHP】PHP开发必备配置 - Windows]] 中提到过这个工具的安装，这里不再重复介绍。
Composer 命令
Composer 命令的常用命令如下：
查看Composer版本
composer --versin案例：
C:\Users\adong>composer --version
Composer version 2.4.4 2022-10-27 14:39:29升级将默认升到最新版本
composer self-update友情提示： 版本升级命令将会从官方版本去下载composer,phar镜像,速度将受限！强烈建议全局配置加速镜像
Composer 自我诊断
使用Composer 进行自我诊断的代码如下：
composer diagnose参考案例如下：
C:\Users\adong>composer diagnose
Checking platform settings: OK
Checking git settings: OK git version 2.37.0
Checking http connectivity to packagist: OK
Checking https connectivity to packagist: OK
Checking HTTP proxy: OK
Checking github.com rate limit: OK
Checking disk free space: OK
Checking pubkeys:
Tags Public Key Fingerprint: 57815BA2 7E54DC31 7ECC7CC5 573090D0 87719BA6 8F3BB723 4E5D42D0 84A14642
Dev Public Key Fingerprint: 4AC45767 E5EC2265 2F0C1167 CBBB8A2B 0C708369 153E328C AD90147D AFE50952
OK
Checking composer version: OK
Composer version: 2.4.4
PHP version: 7.4.33
PHP binary path: E:\Program Files\php74\php.exe
OpenSSL version: OpenSSL 1.1.1s 1 Nov 2022
cURL version: 7.70.0 libz 1.2.12 ssl OpenSSL/1.1.1s
zip: extension present, unzip not available, 7-Zip not available清楚缓存
清楚缓存的命令如下
composer clear具体案例如下：
C:\Users\adong>composer clear
Cache directory does not exist (cache-vcs-dir):
Clearing cache (cache-repo-dir): C:\Users\adong\AppData\Local\Composer\repo
Clearing cache (cache-files-dir): C:\Users\adong\AppData\Local\Composer\files
Clearing cache (cache-dir): C:\Users\adong\AppData\Local\Composer
All caches cleared.
项目更新 composer.lock
composer update --lock个人测试案例如下：
C:\Users\adong>composer update --lock
Composer could not find a composer.json file in C:\Users\adong
To initialize a project, please create a composer.json file. See https://getcomposer.org/basic-usage调试
Composer调试只需要在命令前加上-vvv就可以打印出错信息
例如下载laravel命名为blog的项目
composer -vvv create-project laravel/laravel blog安装依赖包
安装依赖包需要在指定项目的根路径执行下面的操作：
composer install更新依赖包
该命令仅限在项目根目录操作
更新所有依赖包
composer update更新指定依赖包
composer update monolog/monolog更新多个指定依赖包
composer update monolog/monolog symfony/dependency-injection根据通配符匹配更新依赖包
composer update monolog/monolog symfony/*移除依赖包
移除指定依赖包
composer remove monolog/monolog根据通配符匹配移除依赖包
composer remove monolog/monolog symfony/*搜索依赖包
搜索依赖包：输出包及其描述信息
composer search monolog使用案例如下：
C:\Users\adong>composer search monolog
monolog/monolog Sends your logs to files, sockets, inboxes, databases and various web services
symfony/monolog-bundle Symfony MonologBundle
symfony/monolog-bridge Provides integration for Monolog with various Symfony components
symfony/debug-bundle Provides a tight integration of the Symfony VarDumper component and the Serv...
maxbanton/cwh AWS CloudWatch Handler for Monolog library
easycorp/easy-log-handler ! Abandoned ! A handler for Monolog that optimizes log me...
theorchard/monolog-cascade Monolog extension to configure multiple loggers in the blink of an eye and a...
bramus/monolog-colored-line-formatter Colored Line Formatter for Monolog
wazaari/monolog-mysql A handler for Monolog that sends messages to MySQL
logentries/logentries-monolog-handler A handler for Monolog that sends messages to Logentries.com.
inpsyde/logzio-monolog Logz.io integration for Monolog
newrelic/monolog-enricher Monolog components to enable New Relic Logs
cmdisp/monolog-microsoft-teams Monolog Handler for sending messages to Microsoft Teams using the Incoming W...
inpsyde/wonolog Monolog-based logging package for WordPress.
amphp/log Non-blocking logging for PHP based on Amp and Monolog.只搜索包，可以添加 --only-name选项，如下所示
composer search --only-name monolog执行命令的返回结果较多：
根据通配符搜索依赖包
composer search mono*案例如下：
C:\Users\adong>composer search mono*
mead-steve/mono-snag Bugsnag integration for monolog. An abstract handler that sends messages to Bugsnag
digikraaft/mono-php PHP Implementation of Mono API
codeat3/blade-mono-icons A package to easily make use of Mono Icons in your Laravel Blade views.
yzen.dev/mono-processor This Processor will display in the logs bread crumbs by which you can more quickly and accurately identify the cause of the error.
remdex/livehelperchat Live Helper Chat - live support for your website. Featuring web and desktop clients. Compatible Windows, Linux, Mac. Desktop client powered by QT. Supports mobile phones based on XMPP se...
aedart/athenaeum Athenaeum is a mono repository; a collection of various PHP packages
druidfi/mona-plugin Mona Composer Plugin for Drupal 7 sites
dbp/relay-mono-connector-payunity-bundle A PayUnity connector for the mono bundle for the Relay API gateway
dbp/relay-mono-connector-generic-bundle A generic connector for the mono payment bundle for the Relay API gateway
dbp/relay-mono-connector-campusonline-bundle A CO payment connector for the mono bundle for the Relay API gateway
dbp/relay-mono-bundle A payment bundle for the Relay API gateway
timitao/monoa
loicjazon/mono
druidfi/mona ! Abandoned ! Example setup using mona-plugin
vldmr-k/mono-acquiring Monobank Acquiring library查看依赖包
该命令仅限项目根目录使用
查看当前项目已安装的依赖包
composer show根据通配符当前项目进行筛选
composer show laravel*查看当前项目指定依赖包
composer show laravel/tinker