从json获取信息

Question

我的节点应用程序生成格式错误：

{ [Error: Username already exists]
  index: 0,
  instance:
   { username: [Getter/Setter],
     name: [Getter/Setter],
     email: [Getter/Setter],
     password: [Getter/Setter],
     birthday: [Getter/Setter],
     gender: [Getter/Setter],
     join_date: [Getter/Setter],
     id: [Getter/Setter] } }

如何访问“用户名已存在”文本？输出高于对象的console.log（）。

谢谢

Answer 1

实际上是一个express.js错误对象，用于检索用户需要的消息error.message