每次编辑文档时，Mongoose 都会触发预钩子答案

【问题标题】：Mongoose fire pre hook every time a doc is edited每次编辑文档时，Mongoose 都会触发预钩子
【发布时间】：2022-09-22 21:54:12
【问题描述】：

我有这个模式和像basicSalary这样的字段可以由管理员通过仪表板UI编辑，预保存钩子第一次可以正常工作，但是如果一个字段被编辑，它不会动态计算totalEarnings，@987654323 @ 和netSalary，所以每次更改文档时我都需要预先保存钩子以触发，该怎么做？

const salariesSchema = mongoose.Schema({
  employeeId: {
    type: mongoose.Schema.Types.ObjectId,
    ref: \"employee\",
    required: true,
  },
  month: { type: String, required: true },
  year: { type: String, required: true },
  basicSalary: { type: Number, default: 0, required: true },
  accomodation: { type: Number, default: 0 },
  transportation: { type: Number, default: 0 },
  bonus: { type: Number, default: 0 },
  SSC: { type: Number, default: 0 },
  incomeTax: { type: Number, default: 0 },
  medicalInsurance: { type: Number, default: 0 },
  loan: { type: Number, default: 0, default: null },
  totalEarnings: { type: Number },
  totalDeductions: { type: Number },
  netSalary: { type: Number },
});
salariesSchema.pre(\"save\", function (next) {
  this.SSC = this.basicSalary * 0.07;
  this.totalEarnings =
    this.basicSalary + this.accomodation + this.transportation + this.bonus;
  this.totalDeductions =
    this.incomeTax + this.medicalInsurance + this.loan + this.SSC;
  this.netSalary = this.totalEarnings - this.totalDeductions;
  next();
});

标签： mongodb mongoose mongoose-schema

【解决方案1】：

您应该为其他类型的查询创建单独的 pre 挂钩。例如，您可以添加更新一pre钩子：

salariesSchema.pre("save", function (next) {
  this.SSC = this.basicSalary * 0.07;
  this.totalEarnings =
    this.basicSalary + this.accomodation + this.transportation + this.bonus;
  this.totalDeductions =
    this.incomeTax + this.medicalInsurance + this.loan + this.SSC;
  this.netSalary = this.totalEarnings - this.totalDeductions;
  next();
});

salariesSchema.pre('updateOne', function() {
  this.SSC = this.basicSalary * 0.07;
  this.totalEarnings =
    this.basicSalary + this.accomodation + this.transportation + this.bonus;
  this.totalDeductions =
    this.incomeTax + this.medicalInsurance + this.loan + this.SSC;
  this.netSalary = this.totalEarnings - this.totalDeductions;
  next();
});

【讨论】：

但它说Salary.pre 不是函数。
我更新了我的答案。你能再试一次吗？