有没有办法排除等于null的lessons.lesson_id?我从以前的答案中得到以下内容,但它仍然提供无效的课程.lesson_id
newList.add(test.id.ToString());
newList.add(test.timeSlot + test.dateSlot);
我正在尝试阻止使用null的lesson_id显示
module.exports.getClasses = function(id, callback){
Class.findById(id)
.populate(
{path: 'lessons.lesson_id',
model: 'Lesson', $ne: null}
).exec(callback)
}
var classSchema = new Schema({
title: { type: String, required: true },
lessons: [{
_id: false,
lesson_id: {type: mongoose.Schema.Types.ObjectId, ref: 'Lesson'}
}],
});
答案 0 :(得分:0)
So your ClassSchema is a touch off, I think you may find this will work better based on your requirements:
var classSchema = new Schema({
title: { type: String, required: true },
lessons: [{type: mongoose.Schema.Types.ObjectId, ref: 'Lesson'}],
});