获取对象数组中所有指定元素的总和

本文介绍了获取对象数组中所有指定元素的总和的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有一组对象作为跟随者

I have an array of objects as folllows

[ {"width":128.90663423245883,"height":160,"X":0,"Y":140}, {"width":277.0938568683375,"height":263,"X":128.90663423245883,"Y":37}, {"width":264.8267031014369,"height":261,"X":277.0938568683375,"Y":39}, {"width":229.14003389179788,"height":60,"X":264.8267031014369,"Y":240}, {"width":10.032771905968888,"height":177,"X":229.14003389179788,"Y":123} ]

我希望编写一个函数，该函数在当前对象之前获取对象中所有宽度"元素的总和.

I am looking to write a function that gets the sum of all 'width' elements in the object before the current.

类似的东西:

function getAllBefore(current) { // here i want to get the sum of the previous 4 'width' elements in the object } getAllBefore(obj[5]);

推荐答案

要获得更简单，更可重用的代码，请将对象和索引传递给该方法，如下所示:

For an easier and more reusable code pass to the method the object and the index, as follows:

function getAllBefore(obj, index){ var sum=0; for(var i=0; i<index; i++){ sum+=obj[i].width; } return sum; }

并这样称呼它:

getAllBefore(obj, 5);