風信建站Laravel項目開發過程中，在初始化項目過程中This package requires php ^7.1.3 but your PHP version (7.0.12) does not satisfy that requirement錯誤的解決方法：

分析：以下錯誤為php版本太低導致，所以我們需要清理composer.lock文件。

解決方法是：

刪除 composer.lock 文件，重新執行 composer install，這樣就能重新生成 composer.lock 文件了。

$ laravel new katCMS
Crafting application...
Loading composer repositories with package information
Installing dependencies (including require-dev) from lock file
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - This package requires php ^7.1.3 but your PHP version (7.0.12) does not satisfy that requirement.
  Problem 2
    - Installation request for doctrine/inflector v1.3.0 -> satisfiable by doctrine/inflector[v1.3.0].
    - doctrine/inflector v1.3.0 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 3
    - Installation request for laravel/framework v5.6.26 -> satisfiable by laravel/framework[v5.6.26].
    - laravel/framework v5.6.26 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 4
    - Installation request for symfony/console v4.1.1 -> satisfiable by symfony/console[v4.1.1].
    - symfony/console v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 5
    - Installation request for symfony/css-selector v4.1.1 -> satisfiable by symfony/css-selector[v4.1.1].
    - symfony/css-selector v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 6
    - Installation request for symfony/debug v4.1.1 -> satisfiable by symfony/debug[v4.1.1].
    - symfony/debug v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 7
    - Installation request for symfony/event-dispatcher v4.1.1 -> satisfiable by symfony/event-dispatcher[v4.1.1].
    - symfony/event-dispatcher v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 8
    - Installation request for symfony/finder v4.1.1 -> satisfiable by symfony/finder[v4.1.1].
    - symfony/finder v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 9
    - Installation request for symfony/http-foundation v4.1.1 -> satisfiable by symfony/http-foundation[v4.1.1].
    - symfony/http-foundation v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 10
    - Installation request for symfony/http-kernel v4.1.1 -> satisfiable by symfony/http-kernel[v4.1.1].
    - symfony/http-kernel v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 11
    - Installation request for symfony/process v4.1.1 -> satisfiable by symfony/process[v4.1.1].
    - symfony/process v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 12
    - Installation request for symfony/routing v4.1.1 -> satisfiable by symfony/routing[v4.1.1].
    - symfony/routing v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 13
    - Installation request for symfony/translation v4.1.1 -> satisfiable by symfony/translation[v4.1.1].
    - symfony/translation v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 14
    - Installation request for symfony/var-dumper v4.1.1 -> satisfiable by symfony/var-dumper[v4.1.1].
    - symfony/var-dumper v4.1.1 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 15
    - Installation request for doctrine/instantiator 1.1.0 -> satisfiable by doctrine/instantiator[1.1.0].
    - doctrine/instantiator 1.1.0 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 16
    - Installation request for myclabs/deep-copy 1.8.1 -> satisfiable by myclabs/deep-copy[1.8.1].
    - myclabs/deep-copy 1.8.1 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 17
    - Installation request for nunomaduro/collision v2.0.3 -> satisfiable by nunomaduro/collision[v2.0.3].
    - nunomaduro/collision v2.0.3 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 18
    - Installation request for phpunit/php-code-coverage 6.0.7 -> satisfiable by phpunit/php-code-coverage[6.0.7].
    - phpunit/php-code-coverage 6.0.7 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 19
    - Installation request for phpunit/php-file-iterator 2.0.1 -> satisfiable by phpunit/php-file-iterator[2.0.1].
    - phpunit/php-file-iterator 2.0.1 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 20
    - Installation request for phpunit/php-timer 2.0.0 -> satisfiable by phpunit/php-timer[2.0.0].
    - phpunit/php-timer 2.0.0 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 21
    - Installation request for phpunit/php-token-stream 3.0.0 -> satisfiable by phpunit/php-token-stream[3.0.0].
    - phpunit/php-token-stream 3.0.0 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 22
    - Installation request for phpunit/phpunit 7.2.6 -> satisfiable by phpunit/phpunit[7.2.6].
    - phpunit/phpunit 7.2.6 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 23
    - Installation request for sebastian/comparator 3.0.1 -> satisfiable by sebastian/comparator[3.0.1].
    - sebastian/comparator 3.0.1 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 24
    - Installation request for sebastian/diff 3.0.1 -> satisfiable by sebastian/diff[3.0.1].
    - sebastian/diff 3.0.1 requires php ^7.1 -> your PHP version (7.0.12) does not satisfy that requirement.
  Problem 25
    - laravel/framework v5.6.26 requires php ^7.1.3 -> your PHP version (7.0.12) does not satisfy that requirement.
    - laravel/tinker v1.0.7 requires illuminate/console ~5.1 -> satisfiable by laravel/framework[v5.6.26].
    - Installation request for laravel/tinker v1.0.7 -> satisfiable by laravel/tinker[v1.0.7].

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