Question

如何附加一个名为'Index'的键，其值为下面数组的词典索引？在此之前，数组应按时间戳排序，以便TimeStamp：111首先出现，TimeStamp：222出现在第二个等等。

例如，请参阅下面的原始数组

items = [
            {Id: "01", Name: "A", Price: "1.00", Quantity: "1",TimeStamp:111},
            {Id: "02", Name: "B", Price: "10.00", Quantity: "1",TimeStamp:222},
            {Id: "04", Name: "C", Price: "9.50", Quantity: "10",TimeStamp:434},
            {Id: "03", Name: "a", Price: "9.00", Quantity: "2",TimeStamp:545},
            {Id: "06", Name: "b", Price: "100.00", Quantity: "2",TimeStamp:676},
            {Id: "05",Name: "c", Price: "1.20", Quantity: "2",TimeStamp:777}
        ];

生成的数组应如下所示：

items = [
    {Id: "01", Name: "A", Price: "1.00", Quantity: "1",TimeStamp:111,Index:1},
            {Id: "02", Name: "B", Price: "10.00", Quantity: "1",TimeStamp:222,Index:2},
            {Id: "04", Name: "C", Price: "9.50", Quantity: "10",TimeStamp:434,Index:3},
            {Id: "03", Name: "a", Price: "9.00", Quantity: "2",TimeStamp:545,Index:4},
            {Id: "06", Name: "b", Price: "100.00", Quantity: "2",TimeStamp:676,Index:5},
            {Id: "05",Name: "c", Price: "1.20", Quantity: "2",TimeStamp:777,Index:6}
        ];

这是我的尝试：http://jsfiddle.net/chrisguzman/f7dnfrjf/ 我已经弄清楚如何将一个项目附加到每个字典，但不知道如何附加其各自的迭代器。

此外，这里是角度js（奖励点，如果有办法用角度）：http://codepen.io/chriscruz/pen/GgjGvO?editors=101

Answer 1

索引从0开始，因此您需要为每个索引添加+1，例如

items.forEach(function (d, index) {
    d.Index = index + 1;
});

演示：http://jsfiddle.net/f7dnfrjf/1/

Angular demos：

http://codepen.io/pen/ZYpRag - 索引显示为2,3,5,6
http://codepen.io/pen/zxKapG - 索引显示为1,2,3,4

Answer 2

运行时系统将3个参数传递给.forEach()：第一个是数组元素，第二个是索引，第三个是数组本身。

因此：

items.forEach(function (d, i) {
    d.Index = i;
});

如何使用Javascript将迭代器索引号附加到数组中的每个项目？

2 个答案: