javascript - 添加来自不同数组对象的所有相同元素

Question

我需要添加不同对象的相同元素并返回final volumn{ mono: color:}。请参阅下面的代码:

//function to add different objects
   function addMonoColorVolumn(objects) {
     var volumn = {
       mono: [],
       color: []
     };
     var mono = 0,
       color = 0;

     function addValusCB(obj) {
       if (obj.monoTotal) {
         mono += obj.monoTotal;
         volumn.mono.push(mono);
       }
       if (obj.colorTotal) {
         color += obj.colorTotal;
         volumn.color.push(color);
       }
     }
     if (objects.length) {
       //if objects length is more then 0 than call the callback fn.
       objects.forEach(addValusCB);
     }
     return volumn;
   }


   function main() {
     var testObjects = [{
       monoTotal: 100,
       colorTotal: 200
     }, {
       monoTotal: 100,
       colorTotal: 200
     }, {
       monoTotal: 100,
       colorTotal: 200
     }];
     console.log(testObjects);
     console.log(addMonoColorVolumn(testObjects)) //output should be object{color:1200,mono:600}
   }
   main();

我是 javascript 新手，请指导我解决这个问题。这是我的 fiddle Running fiddel .

Answer 1

您可以使用Array#reduce并对您需要的属性求和。

var testObjects = [{ monoTotal: 100, colorTotal: 200 }, { monoTotal: 100, colorTotal: 200 }, { monoTotal: 100, colorTotal: 200 }],
    sum = testObjects.reduce(function (r, o) {
        ['mono', 'color'].forEach(function (k) {
            r[k] = (r[k] || 0) + o[k + 'Total'];
        });
        return r;
    }, {});

console.log(sum);