Add another property to all objects in array

Question

Sorry new to typescript, I have this array of object, i need to insert another property type with value Customer for all objects.

//this is printed out in browser's developer mode, that's why the index is there
0: {name: "Ken", address: "USA"}
1: {name: "Peter", address: "USA"}

In the final array, it will be:

0: {name: "Ken", address: "USA", type: "Customer"}
1: {name: "Peter", address: "USA", type: "Customer"}

Something like:

this.users.forEach(function (user) {
    user.type: "Customer"
});

Tried to search around but not able to find the answer, how do i achieve the above?

bin liu · Accepted Answer · 2021-08-19 09:22:17Z

2

 this.users = this.users.map(item => ({...item, type: "Customer"}))

answered Aug 19, 2021 at 9:22

bin liu

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Comments

Risalat Zaman · Accepted Answer · 2021-08-19 09:19:31Z

2

Try

this.users = this.users.map(function (user) {
    user.type =  "Customer"
    return user;
});

answered Aug 19, 2021 at 9:19

Risalat Zaman

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Why use map() instead of forEach()? You're mutating the objects itself anyway.

forEach is fine here too. I just tend to use map whenever I am mutating an object. It helps me detect where I am mutating objects in code easily

Quyết · Accepted Answer · 2021-08-19 09:22:34Z

0

Change your user.type: "Customer" to user.type = "Customer" and it should work

let users = [{name: "Ken", address: "USA", type: "Customer"}]

users.forEach(function (user) {
    user.type = "Customer"
});

console.log(users)

answered Aug 19, 2021 at 9:22

Quyết

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