schemas
book.js
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var ObjectId = Schema.Types.ObjectId;
var BookSchema = new Schema({
// some code
});
BookSchema.pre('save',(next) =>{
console.log(this); // 此处 this 输出为 {}
// some code
next();
})
BookSchema.statics = {
fetch: (cb) => {
console.log(this); // 此处 this 输出为 {}
// some code
}
}
module.exports = BookSchema;
models
book.js
var mongoose = require('mongoose');
var BookSchema = require('../schemas/book');
var Book = mongoose.model('book',BookSchema);
module.exports = Book;
routes
books.js
var Book = require('../models/book');
mongoose.connect('mongodb://localhost/readbook');
Book.fetch((err, books) => {
// some code
});
代码中两处输出均为 {}
请指教, O(∩_∩)O谢谢
是 lambda
表达式的问题
但是 why ?
不使用箭头表达式就可以了, 剪头表示会重定绑定this,会影响mongoose