对数组项进行排序并保留相同元素的顺序 [英] Sort array items and preserve order of same elements

问题描述

假设我有这个数组:

var array = [
  { name: "border-color", value: "#CCCCCC" },
  { name: "color", value: "#FFFFFF" },
  { name: "background-color", value: "rgb(0, 0, 0)" },
  { name: "background-color", value: "rgba(0, 0, 0, .5)" }
];

此函数按名称对数组进行排序:

And this function to sort the array by name:

array.sort(function(a, b) {
  if (a.name < b.name) return -1;
  if (a.name > b.name) return 1;
  return 0;
});

ECMAScript语言规范告诉我，:

排序不一定是稳定的(即比较的元素 相等并不一定要保持其原始顺序.

The sort is not necessarily stable (that is, elements that compare equal do not necessarily remain in their original order).

因此，排序后，名称=背景色的两个项目可以按任意顺序出现，即:

So, after sorting, the two items with name = background color could appear in any order i.e.:

[
  { name: "background-color", value: "rgb(0, 0, 0)" },
  { name: "background-color", value: "rgba(0, 0, 0, .5)" },
  ...
]

或

[
  { name: "background-color", value: "rgba(0, 0, 0, .5)" },
  { name: "background-color", value: "rgb(0, 0, 0)" },
  ...
]

如何对数组进行排序，以使具有相同名称的项目保持其相对顺序?我宁愿不对任何内容进行硬编码.

How can I sort the array so that items with same name maintain their relative order? I would rather not hardcode anything.

推荐答案

从理论上讲，在排序之前，您可以跟踪其在数组中的索引，并在排序时将其考虑在内.

Theoretically before sorting you could keep track of its index in the array and take that into account when sorting.

var sortArray = yourarray.map(function(data, idx){
    return {idx:idx, data:data}
})

sortArray.sort(function(a, b) {
  if (a.data.name < b.data.name) return -1;
  if (a.data.name > b.data.name) return 1;
  return a.idx - b.idx
});

var answer = sortArray.map(function(val){
    return val.data
});

这篇关于对数组项进行排序并保留相同元素的顺序的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！