schema中的虚拟属性方法

Posted 2020-08-30 向着太阳生

schema中的虚拟属性方法相当于vue中的计算属性，它是通过已定义的schema属性的计算\组合\拼接得到的新的值

var personSchema = new Schema({
  name: {
    first: String,
    last: String
  }
});

var Person = mongoose.model(‘Person‘, personSchema);
// create a document
var bad = new Person({
    name: { first: ‘Walter‘, last: ‘White‘ }
});

personSchema.virtual(‘name.full‘).get(function () {
  return this.name.first + ‘ ‘ + this.name.last;
});

console.log(‘%s is insane‘, bad.name.full); // Walter White is insane

虚拟属性也可以设置setter

personSchema.virtual(‘name.full‘).set(function (name) {
  var split = name.split(‘ ‘);
  this.name.first = split[0];
  this.name.last = split[1];
});
...
mad.name.full = ‘Breaking Bad‘;
console.log(mad.name.first); // Breaking
console.log(mad.name.last);  // Bad

Note:每个实例文档都能调用schema定义的方法和属性