Most middleware (like bodyParser) is no longer bundled with Express

    在cmd命令行里，输入node app.js

    提示：   

        Error: Most middleware (like bodyParser) is no longer bundled with Express and m

ust be installed separately. Please see https://github.com/senchalabs/connect#mi

ddleware.

  意思是新版express不包含bodyParser了，要单独安装。

npm install body-parser

 注意大小写。

安装完就可以用啦。