如何使用nodejs在mongodb中的每個文檔的字段中添加數字

Question

我的收藏有一個phonenumber字段。 我想在電話號碼前加 91。

{
"_id": "6137392141bbb7723",
"email": "brooke@cagle.com",
"lastname": "Cagle",
"firstname": "Brooke",
"phonenumber":9000000001
},
{
"_id": "6137392141bbe30723",
"email": "brooke@cagle.com",
"lastname": "Cagle",
"firstname": "Brooke",
"phonenumber":9000000002
}

我想像這樣更新我的收藏。

{
"_id": "6137392141bbb7723",
"email": "brooke@cagle.com",
"lastname": "Cagle",
"firstname": "Brooke",
"phonenumber":919000000001
},
{
"_id": "6137392141bbe30723",
"email": "brooke@cagle.com",
"lastname": "Cagle",
"firstname": "Brooke",
"phonenumber":919000000002
}

我正在嘗試使用此代碼，但它沒有更新該字段。

var x = await User.find({});
        x.forEach(async function(d)
            { 
                var phone = d.phonenumber;  
                var newPhoneNumber = 910000000000+phone;
                console.log(newPhoneNumber);

                //update 
            await User.updateMany({},{$set:{phonenumber:newPhoneNumber}},
                {
                    new: true, 
                    runValidators : true
                });
            })

對於這樣的所有文檔，我只得到一個值：

{
"_id": "6137392141bbb7723",
"email": "brooke@cagle.com",
"lastname": "Cagle",
"firstname": "Brooke",
"phonenumber":919000000001
},
{
"_id": "6137392141bbe30723",
"email": "brooke@cagle.com",
"lastname": "Cagle",
"firstname": "Brooke",
"phonenumber":919000000001
},
{
"_id": "6137392141bbe30723",
"email": "brooke@cagle.com",
"lastname": "Cagle",
"firstname": "Brooke",
"phonenumber":919000000001
}

我不知道這種方法是否正確。

Answer 1

db.collection.update(
  {}, //To match all documents
  [{ $set: { phonenumber: { $concat: [ "91", "$phonenumber" ] } } }], //Concatenate 91 and the value in the field
  { multi: true }
)

這適用於 4.2 的 mongo 版本。 這是用於更新查詢的聚合管道。

參考

Answer 2

我找到了解決方案。 也許，這行得通，

let mobile = 9876543210;
let phone = `91${mobile}`;
let final = Number(phone)
console.log(typeof(final), final+3);

所以，

var phone = d.phonenumber;
var newPhoneNumber = Number(`91${phone}`);
console.log(newPhoneNumber);

閱讀有關 Number() 的更多信息： https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number