如何在一对多关系中显示详细信息

Question

在我的例子中，一个主类别有许多子类别。

定义的主分类模型：

const MainCategorySchema = mongoose.Schema({
mainCategoryName: {
type: String,
unique: true,
required: true,
},
});

子类别模型定义的

const SubCategorySchema = mongoose.Schema({
subCategoryName: {
type: String,
unique: true,
required: true,
},
main_category: {
type: mongoose.Schema.Types.ObjectId,
ref: "MainCategory",
},
});
module.exports.getAllSubCategories = function (callback) {
SubCategory.find(callback);
};

路线

router.get( "/subCategories",
passport.authenticate("jwt", { session: false }),
(req, res) => {
SubCategory.getAllSubCategories((err, subCategory) => {
if (err) {
let message = "No category";
return res.json({
success: false,
message,
});
} else {
return res.send(subCategory);
}
});
}
);

如何显示mainCategoryName和subCategoryName？

Answer 1

您需要像这样填充main_category：

router.get("/subCategories",
passport.authenticate("jwt", { session: false }), (req, res) => {
SubCategory.find()
.populate("main_category")
.exec((err, subCategory) => {
if (err) {
let message = "No category";
return res.json({
success: false,
message
});
} else {
return res.send(subCategory);
}
});
}
);