javascript - 比较每个数值的总和后如何对数组元素进行排序和列出

Question

此代码仅返回数值总和的顺序，如何返回按最大总和排列在顶部的列表中的数组元素？例如，结果应该是:

"1234-2722-2343-2842"
"1234-2722-2343-2345"
"1234-2322-2343-2342"

代码:

var addSum = function(ccNum) {
    var sum = 0;
    for (var i=0; i<ccNum.length; i++ ) {
        var eachLetter = ccNum.charAt(i);
        if (!isNaN(eachLetter)) {
            sum += +eachLetter;
        }
    }
    return sum; 
};

var ccNums = ["1234-2322-2343-2342","1234-2722-2343-2345", "1234-2722-2343-2842"];

var checkNums = [];

for (var i=0; i<ccNums.length; i++) {
    var ccNum = ccNums[i];
    var sum = addSum(ccNum);
    console.log("The checksum of CC number:"+ccNum+" is "+sum);
    checkNums.push(sum); 
}

checkNums.sort(function(a,b) {
    return b-a;
});

console.log(checkNums);

Answer 1

使用String.replace、String.split、Array.map、Array.filter和的解决方案数组.reduce:

var ccNums = ["1234-2322-2343-2342","1234-2722-2343-2345", "1234-2722-2343-2842"],
    getSum = function(num){
        return num.replace("-", "").split("").map(Number).filter(Boolean).reduce(function(prev, next){
            return prev + next;
        });
    };

ccNums.sort(function (a, b) {
    return getSum(b) - getSum(a);
});

console.log(ccNums);

输出:

["1234-2722-2343-2842", "1234-2722-2343-2345", "1234-2322-2343-2342"]