我如何在 Lodash 中做到这一点？

Question

I have a array like structure from database results

var arr = [{name: 'a', age: 23}, {name: 'b', age: 24}, {name: 'c', age: 35}] 

I want to create a new object with values as key and value like below:

var new_arra  = {a: 23, b: 24, c: 35}

How can I do this in lodash?

I tried the below method:

var result = _.forEach(results, function(index) {
    var result = _.map(index, function(value, prop) {
        return {prop: prop, value: value};
    });
});

Answer 1

Using ES5 - iterate with Array#reduce with initial value of an empty object. On each iteration set the name as key, and the age as value.

 var arr = [{name: 'a', age: 23}, {name: 'b', age: 24}, {name: 'c', age: 35}]; var result = arr.reduce(function(obj, o) { obj[o.name] = o.age; return obj; }, {}); console.log(result);

Using ES6 - Iterate with Array#map get the values using destructuring , and set using computed property names . Combine all to a single object by using Object#assign with the spread syntax :

 const arr = [{name: 'a', age: 23}, {name: 'b', age: 24}, {name: 'c', age: 35}]; const result = Object.assign({}, ...arr.map(({ name, age }) => ({ [name]: age }))); console.log(result);

Answer 2

You can do it with pure JS this way:

 var arr = [{ name: 'a', age: 23 }, { name: 'b', age: 24 }, { name: 'c', age: 35 }] var result = {}; arr.forEach(function(item) { result[item.name] = item.age }); console.log(result);

Another way with reduce :

 var arr = [{ name: 'a', age: 23 }, { name: 'b', age: 24 }, { name: 'c', age: 35 }]; var result = arr.reduce(function(store, item) { store[item.name] = item.age; return store; }, {}); console.log(result);

Answer 3

you need these two line only

let newData = {};
arr.map((item)=>newData[item.name]=item.age);

console.log(newData);

or you can also do it using lodash

 let newData = {};
 _.map(arr,(item)=>newData[item.name]=item.age);

Answer 4

That's simple.

All you need to do is loop through each data and insert it into a new empty object. Ex.

let new_arra = {};

_.each(arr, a => {
 new_arra[a.name] = a.age
});

But, if you really wanna learn more you can read this blog: Noobie Programmer: Lodas - The best 3rd party library for react and javascript developers

it teaches you the basics. Once you mastered it you can do any complex data structures.