• 升级composer版本

composer self-update

#回退版本
composer self-update --rollback

#查看当前安装的扩展包
composer show -i

#安装
composer install
composer i

#list
composer list


#查看版本
composer show topthink/*
composer show phpunit/phpunit

#安装 
composer require topthink/topthink
#安装指定版本
composer require topthink/topthink 1.0.*


#composer卸载扩展包
composer remove phpunit/phpunit

安装dev插件

composer require phpunit/phpunit --dev

回退版本

#回到版本1
composer self-update --1

#切换到指定版本
composer self-update 2.0.14