Question

我正在尝试从我的jobs对象中获取位置字段，但是当我将location.address放在例如js中语法错误时。

这是我的常量，地址，城市和邮政编码的一切都很好。

const { title, avatar, company, postDate, jobType, payment, duration, description, address, city, postcode } = this.props.navigation.state.params;

这是我的数据库计划

jobs: [{
      title: {type: String},
      company: {type: String},
      avatar: {type: String},
      created: {type: Boolean},
      applied: {type: Boolean},
      description: {type: String},
      location: [{
          address: {type: String},
          postcode: {type: String},
          city: {type: String}
      }],
      jobType: {type: String},
      payment: {type: String},
      duration: {type: String},
      postDate: {type: Date},
      expDate: {type: Date}
  }]

Answer 1

location是array个对象。你必须使用一些循环来访问它的属性，如

location.forEach(e=>console.log(e.address))

这可能是你的表达

const { title, avatar, company, postDate, jobType, payment, duration, description, location } = this.props.navigation.state.params;

Answer 2

你不能在数组上点。

您的地址嵌套在数组中。

  location: [{
      address: {type: String},
      postcode: {type: String},
      city: {type: String}
  }]

要访问它，您需要像这样

对其进行索引

jobs[0].location[0].address

Answer 3

location是一个数组。据推测，如果每个数据的位置是单个的，则不必是数组。取代

...
location: [{
          address: {type: String},
          postcode: {type: String},
          city: {type: String}
      }],
...

到

...
location: {
          address: {type: String},
          postcode: {type: String},
          city: {type: String}
      },
...

并简单地使用location.address

但它应该是一个数组，就像我们使用数组一样工作

第一元素

location[0].address

第二元素

location[1].address

对于所有元素

location.forEach(varName){
varName.address
}

当字符串在另一个字符串中时，如何从DB获取数据？

3 个答案: