下面由composer教程栏目给大家介绍composer require指定版本的方法，希望对需要的朋友有所帮助！
默认
composer require endroid/qr-code
指定版本
composer require endroid/qr-code 1.9.3
# composer require endroid/qr-code 1.9.3
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Package operations: 0 installs, 1 update, 0 removals
- Removing endroid/qr-code (2.5.1)
- Installing endroid/qr-code (1.9.3): Downloading (100%)
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Writing lock file
Generating autoload files