OK了    npm init

全局的webpack 及 cli还有局部的都按装了吗 ？  npm init

安装node.js

{"name": "vue-todo","version": "1.0.0","main": "index.js","scripts": {"test": "echo \"Error: no test specified\" && exit 1","build": "webpack --config webpack.config.js","dev": "webpack --config webpack.config.js"},"author": "","license": "ISC","description": "","dependencies": {"cross-env": "^5.2.0","css-loader": "^2.1.0","vue": "^2.5.22","vue-loader": "^15.6.1","vue-template-compiler": "^2.5.22","webpack": "^4.29.0"},"devDependencies": {"webpack-cli": "^3.2.1"}}

自己加一个试试看。