javascript - 添加对象数组中包含的值

Question

我将如何添加对象内的所有值？

例如 amoutpay": ["4222","1000"] 会给我 5222

这是我的对象:

{
    "amoutpay": [ "4222", "1000" ],
    "amtpending": [ "778", "4000" ],
    "totalcost": [ "5000", "5000" ],
    "coursename": [ "Office Automation", "ajaba" ]
}

我想要的是将值添加到变量中。我会使用拆分吗？

var a =
var b =
var c =

Answer 1

您可以使用Array.prototype.reduce()如下图:

var obj = {
    "amoutpay": [ "4222", "1000" ],
    "amtpending": [ "778", "4000" ],
    "totalcost": [ "5000", "5000" ],
    "coursename": [ "Office Automation", "ajaba" ]
},
    
    a = obj.amoutpay.reduce(function(prevVal, curVal, curInd) {
        return +prevVal + +curVal;
    }),
    b = obj.amtpending.reduce(function(prevVal, curVal, curInd) {
        return +prevVal + +curVal;
    }),
    c = obj.totalcost.reduce(function(prevVal, curVal, curInd) {
        return +prevVal + +curVal;
    });

console.log( a, b, c );

或者您可以更进一步，定义自己的数组方法，例如 Array.prototype.sum():

var obj = {
        "amoutpay": [ "4222", "1000" ],
        "amtpending": [ "778", "4000" ],
        "totalcost": [ "5000", "5000" ],
        "coursename": [ "Office Automation", "ajaba" ]
    };

Array.prototype.sum = function() {
    return this.reduce(function( prv, cur, ind ) {
        return +prv + +cur;
    });
};

var a = obj.amoutpay.sum(),
    b = obj.amtpending.sum(),
    c = obj.totalcost.sum();

console.log( a, b, c );