Laravel运行出错RuntimeException No application encryption key has been specified.

①在项目根目录放置.env文件

.env

APP_NAME=LaravelAPP_ENV=localAPP_KEY=APP_DEBUG=trueAPP_LOG_LEVEL=debugAPP_URL=http://localhostDB_CONNECTION=mysqlDB_HOST=127.0.0.1DB_PORT=3306DB_DATABASE=homesteadDB_USERNAME=homesteadDB_PASSWORD=secretBROADCAST_DRIVER=logCACHE_DRIVER=fileSESSION_DRIVER=fileSESSION_LIFETIME=120QUEUE_DRIVER=syncREDIS_HOST=127.0.0.1REDIS_PASSWORD=nullREDIS_PORT=6379MAIL_DRIVER=smtpMAIL_HOST=smtp.mailtrap.ioMAIL_PORT=2525MAIL_USERNAME=nullMAIL_PASSWORD=nullMAIL_ENCRYPTION=nullPUSHER_APP_ID=PUSHER_APP_KEY=PUSHER_APP_SECRET=

②在项目目录下运行:

php artisan key:generate

该命令会生成APP_KEY并写入到.env文件中，重新运行