composer (一)

Reference Document composer: composer Chinese network

1. Installation composer: Windows installation: using the installation program: https: //docs.phpcomposer.com/00-intro.html#Using-the-Installer
2. Make sure PHP commands are global to PHPstudy for example: PHPstudy just install it, open cmd, enter PHP -v command to see if PHP is global, not, configure the environment variables.
3. Let me talk about the PHP configuration environment variable: find the "Advanced System Settings" (choose one way to find environment variables)
   1. ① My Computer - Properties - Advanced - Environment Variables ②win8,10 direct "View Advanced System Settings" in the search box search - Environment Variables
   2. Find the variable "Path" (win10 with ②) ① back in the original plus "; D: / xammp / php" (directory php.exe where, in front there is a;) ② or by adding a new "D: / xammp / php " 
   3. Reopen cmd: win + R, enter php -v (see php version information)