我想向Blog
对象添加几个Categories
个对象,之后可以访问Blog的第一个类别。
var ObjectId = mongoose.Schema.Types.ObjectId;
var categorySchema = mongoose.Schema({
title: String,
blogs: [{ type: ObjectId, ref: 'Blog' }]
})
var blogSchema = mongoose.Schema({
title: String,
description: String,
category: [{ type: ObjectId, ref: 'Category' }],
created: {type: Number, default: new Date().getTime()}
})
var Category = mongoose.model('Category', categorySchema)
var Blog = mongoose.model('Blog', blogSchema)
exports.addBlog = function (object, callback) {
Blog({
title: object.title,
description: object.description,
category: object.category //array of sting ObjectID's - ['',''] – from multiselect box
}).save(function (err, _) {
Blog
.find({title: _.title})
.populate('category')
.exec(function (err, __) {
if (err) return handleError(err);
console.log('Category is ', __.category[0].title);
})
callback(err, _);
});
}
结果我得到了:
TypeError: Cannot read property '0' of undefined
似乎Mongoose在最后一个回调(__)中找不到对象,但我检查过 - _.title
是有效的。如何填充它?感谢。
答案 0 :(得分:1)
问题是Blog.find()
返回一个数组,我应该使用__[0].category[0].title
或找到findOne()
。