composer update install require 三个命令的的别

1.当前项目没有vendor目录、 composer.json和ccomposer.lock文件

• composer update

S D:\phpstudy_pro\WWW\aa> composer update
Composer could not find a composer.json file in D:\phpstudy_pro\WWW\aa
To initialize a project, please create a composer.json file as described in the https://getcomposer.org/ "Getting Started" section

没有任何执行结果

 

• composer require 

PS D:\phpstudy_pro\WWW\aa> composer require
Search for a package

 

 

 

 生成composer.json文件，目前没有下载依赖包,接下来通过Search for package安装monolog/monolog

PS D:\phpstudy_pro\WWW\aa> composer require
Search for a package: monolog/monolog                //输入要安装的依赖包

Enter the version constraint to require (or leave blank to use the latest version): 1.1.*                    //输入版本号

Search for a package:
./composer.json has been created
Running composer update monolog/monolog
Loading composer repositories with package information
Updating dependencies
Lock file operations: 1 install, 0 updates, 0 removals
  - Locking monolog/monolog (1.1.0)
Writing lock file
Installing dependencies from lock file (including require-dev)
Package operations: 1 install, 0 updates, 0 removals
  - Installing monolog/monolog (1.1.0): Extracting archive
1 package suggestions were added by new dependencies, use `composer suggest` to see details.
Generating autoload files
PS D:\phpstudy_pro\WWW\aa>

　　

 

 

项目根目录生成了vendor目录，composer.json和ccomposer.lock文件

 

• composer install

PS D:\phpstudy_pro\WWW\aa> composer install
Composer could not find a composer.json file in D:\phpstudy_pro\WWW\aa
To initialize a project, please create a composer.json file as described in the https://getcomposer.org/ "Getting Started" section
PS D:\phpstudy_pro\WWW\aa>

没有composer.json无法安装

 

2.只有composer.json的情况

• composer update

 

PS D:\phpstudy_pro\WWW\aa> composer update

 新生成vendor和composer.lock

 

• composer reqiuire

PS D:\phpstudy_pro\WWW\aa> composer require
Search for a package:  // 这里直接回车不安装任何依赖

 新生成 vendor、composer.lock

 

• composer install

PS D:\phpstudy_pro\WWW\aa> composer install

 提示composer.lock缺失，原因是install命令是根据composer.lock文件安装依赖包， 所以建议使用composer update命令，但是这个命令仍然生成了vendor composer.lock文件。