Question

我使用Node.js和mongoose为应用创建后端，用户可以互相交流。

模式

    var mongoose = require('mongoose');

    var Schema = mongoose.Schema;

    var userSchema = mongoose.Schema({ 
    name : String,
    nick: String, 
    reg_id: String,
    friends: {
      type: Array,
      'default': []
    }
   });
  mongoose.connect('mongodb://localhost:27017/DB');
  module.exports = mongoose.model('users', userSchema);

请求

exports.addfriend = function(reg_id,friend,callback) {

  user.find({reg_id:reg_id},function(err,guy){   

    // found the user, now add his friend
    user.find({name:friend}, function(err,friendFound){
      console.log("trying to add friend to:"+guy)
      console.log("his current friends:"+guy.friends)

      guy.friends.push(friendFound.reg_id)
        callback({'response':guy.name+' is now friends with '+friendFound.name});
    })
  }); 
}

控制台

trying to add friend to:{ _id: 5483d2c76dd64ee412bfe865,
  name: 'Hello',
  nick: 'hey',
  reg_id: 'XXXXXXXXX',
  __v: 0,
  friends: [] }
his current friends:undefined

C:\..\config\requests.js:82
      guy.friends.push(friendFound.reg_id)
TypeError: Cannot call method 'push' of undefined

为什么数组在模式中定义时显示为已定义，并且我正在寻找合适的用户（家伙）？谢谢你的帮助

Answer 1

看来你的guy对象实际上是一串JSON而不是JSON对象。尝试在其上运行JSON解析

exports.addfriend = function(reg_id,friend,callback) {

  user.find({reg_id:reg_id},function(err,guy){   
    guy = JSON.parse(guy); //ADD THIS
    // found the user, now add his friend
    user.find({name:friend}, function(err,friendFound){
      console.log("trying to add friend to:"+guy)
      console.log("his current friends:"+guy.friends)

      guy.friends.push(friendFound.reg_id)
        callback({'response':guy.name+' is now friends with '+friendFound.name});
    })
  }); 
}

无法调用未定义的方法推送（当它被定义时）

1 个答案: