将 JSON 转换为 MongoDB 的整数？

Question

用.post的FORM数据到express/node.js

所有值当前都以字符串形式存储和返回

希望将其中一个数据值 (req.body.quantity) 存储为 INT

//POST
app.post('/add', function (req, res) {    

db.collection('demo').insert(

    {
        "title" : req.body.title,
        "quantity" : req.body.quantity,
    },

        function (err, doc) {

            getAll(res);

        });
});

getAll 当前如下所示：

//EXPRESS NODE.JS
function getAll(res) {

    db.collection('demo').find().sort( { quantity: 1 } ).toArray(function (err, docs) {

     // each doc should look like: { title: 'string', quantity: int}

        res.json({docs: docs});

    });
}

还有工作的.get：

// AJAX    
$('#getBtn').click(function() {
  $.get('http://localhost:9999').
   done(gotAllSuccess).
   fail(gotAllFailure);
});

Answer 1

对于您的代码，我相信这会为您解决问题。

"quantity" : parseInt(req.body.quantity)

---

但是，如果您还没有，我建议您查看Mongoose 之类的内容。这是 MongoDB 的 ORM，它允许您定义描述模型外观的 schemas。在您的情况下，您可以设计如下所示的架构：

// Define your schema somewhere where your app is first initialized.
// You'll also want to open your db connection here somewhere as well, but I'll
// let you figure that out. http://mongoosejs.com
var demoSchema = new mongoose.Schema({ title: String, quantity: Number });
var Demo = mongoose.model('Demo', demoSchema);
// You can just pass in an object literal to mongoose.model instead of
// instantiating a Schema object, but instantiating a Schema object is what
// you'd have to do if you wanted to also add virtual methods/properties.

您还可以在此处将virtual properties 和virtual methods 添加到您的架构中。这些属性和方法不会存储在数据库中。

那么你可以这样做：

// Retrieve the model you created.
var Demo = require('mongoose').model('Demo');

// Request handler for POST requests to /add
app.post('/add', function (req, res) { 
    // Create a new instance of your Demo model and populate it with data.
    var newDemo = new Demo({
        title: req.body.title,
        quantity: req.body.quantity
        // quantity will be converted to a Number because the schema defines it
        // as one.
    });
    // Mongoose documents have persistence methods on them, including save
    // which will update or insert the document depending on whether or not
    // it has an _id already.
    newDemo.save(function (err, newDemo) {
        if (err) return handleError(err);
        // Models also act as the API for querying. Here we find all documents,
        // sort them by quantity ascending, then execute the query.
        // Note: mongoose's query builder syntax below uses promises to make
        // queries very readable :)
        Demo.find().sort('quantity').exec(function (err, demos) {
            if (err) return handleError(err);

            // demos is an array of Demo instances, each with the same
            // persistence methods you saw above.

            // Each demo doc's properties will adhere to the defined type
            // in the schema.
            //
            // { title: 'hello', quantity: 123}

            res.json({ docs: demos });
        });
    });
});

Answer 2

您可以使用Number(...) constructor or function。

Number("123"); // => 123

db.collection('demo').insert(
  {
    "title" : req.body.title,
    "quantity" : Number(req.body.quantity),
  },
  // ...