Convert array of objects and their properties to a

问题:

I tried several of the map functions but could not find a proper way to get what I want. Here is the case:

Object {Results:Array[3]}
   Results:Array[3]
       [0-2]
            0:Object
                   id=null     
                   name: "Rick"
                   upper:"0.67"
            1:Object
                   id="00379321"     
                   name:null
                   upper:"0.46"
            2:Object
                   id="00323113"      
                   name:null
                   upper:null

I want my final result to look like this. I wanted all null values to be removed and all the entries tied up like this in an object.

var finalResult = ["Rick","0.67","00379321","0.46","00323113"];

How can I achieve this result?

回答1:

I suggest to use a fixed array for the keys, because the properties of an object have no order and the order is relevant.

var data = [{ id: null, name: "Rick", upper: "0.67" }, { id: "00379321", name: null, upper: "0.46" }, { id: "00323113", name: null, upper: null }],
    result = [];

data.forEach(function (a) {
    ['id', 'name', 'upper'].forEach(function (k) {
        if (a[k] !== null) {
            result.push(a[k]);
        }
    });
});

console.log(result);

回答2:

_.chain(a)
.map(function(x) {return _.values(x)})
.flatten()
.filter(function(x) {return x != null;})
.value()

回答3:

Small modification for @andrey's code (requires lodash.js)

var a = [{id:null, name: "Rick", upper:"0.67"}, {id:"00379321", name:null, upper:"0.46"}, {id: "00323113",name:null, upper:null}]
_(a)
.map(function(x) {return _.values(x)})
.flatten()
.without(null)
.value()

回答4:

Another underscore solution, similar to the other underscore solutions, but uses reject and the isNull predicate:

var result = _.chain(data)
    .map(_.values)
    .flatten()
    .reject(_.isNull)
    .value();