如何在 Mongodb 中转换 ObjectId？我尝试了不同的方法，但仍然出现错误

Question

架构

//架构设置

var campgroundSchema = new mongoose.Schema({
    name: String,
    image: String,
    description: String
})

var campground = mongoose.model("campground", campgroundSchema)


#The error is where coming from here, don't seem to get the campgrounds diplayed
app.get("/campgrounds/:id", function(req, res){
    //find the campground with provided ID
    campground.findById(req.params.id, function(err, foundCampground){
        if(err){
            console.log(err)
        } else {
            //render show template
            res.render("show", {campground: foundCampground})
        }
    })
})
    

错误信息

** 消息： '在模型“campground”的路径“_id”处，值“5e61150b58e80830240ef790”转换为 ObjectId 失败'， 名称：'CastError'， 模型：模型{露营地}}**

Answer 1

当您创建这样的架构时，您可以传递{ _id: false }

var campgroundSchema = new mongoose.Schema({
    name: String,
    image: String,
    description: String
}, { _id: false })

Answer 2

您可以使用mongoose.Types.ObjectId() 方法将您的字符串转换为MongoId，并将您的字符串作为第一个参数传递。

例如，使用上述方法后，您的代码如下所示

app.get("/campgrounds/:id", function(req, res){
    //find the campground with provided ID
    campground.findById(
      mongoose.Types.ObjectId(req.params.id),
      function(err, foundCampground){
        if(err){
            console.log(err)
        } else {
            //render show template
            res.render("show", {campground: foundCampground})
        }
    })
});