thinkphp6 composer 安装报错  Your requirements could not be resolved to an installable set of packages.

thinkphp6 composer 安装报错  "Your requirements could not be resolved to an installable set of packages."

刚开始用  命令  composer create-project topthink/think ./blog2   安装结果报错

从网上找了半天 终于解决了 , 要加参数 "--ignore-platform-reqs"   命令如下 :

composer create-project --ignore-platform-reqs topthink/think tp8

composer require   --ignore-platform-reqs   topthink/think-multi-app

ok解决 , 但是至于为啥要加   --ignore-platform-reqs  这个参数 后边还得看看

Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - topthink/framework v6.0.3 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
    - topthink/framework v6.0.2 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
    - topthink/framework v6.0.1 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
    - topthink/framework v6.0.0 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
    - Installation request for topthink/framework ^6.0.0 -> satisfiable by topthink/framework[v6.0.0, v6.0.1, v6.0.2, v6.0.3].

  To enable extensions, verify that they are enabled in your .ini files:
    - C:\php\php-7.2.33-1-nts\php.ini
  You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.