在Backbone.js的相反顺序排序字符串 [英] Sorting strings in reverse order with backbone.js

问题描述

我想以按相反的顺序Backbone.js的集合。有关于如何使用整数做previous答复，但没有用绳子。

I'm trying to sort a Backbone.js collection in reverse order. There are previous replies on how to do this with integers, but none with strings.

var Chapter  = Backbone.Model;
var chapters = new Backbone.Collection;

chapters.comparator = function(chapter) {
  return chapter.get("title");
};

chapters.add(new Chapter({page: 9, title: "The End"}));
chapters.add(new Chapter({page: 5, title: "The Middle"}));
chapters.add(new Chapter({page: 1, title: "The Beginning"}));

alert(chapters.pluck('title'));

以上code排序章节中的从A - >以Z ，但我怎么写，从ž排序，一个比较？ - > A

The above code sorts the chapters from A -> Z, but how do I write a comparator that sorts it from Z -> A?

推荐答案

有，你可以用比较函数的两个版本，无论是在 sortBy 版本 - 这是在示例中所示，这有一个参数，或排序 - 你可以返回更多的标准排序功能，其中文档说：

There are two versions of the comparator function that you can use, either the sortBy version - which was shown in the example, which takes one parameter, or sort - which you can return a more standard sort function, which the documentation says:

sortBy比较函数接受一个模型，并返回一个数字或字符串值通过该模型应该相对于其他订购。 之​​类的比较函数采取两种模式，并返回-1，如果，如​​果他们是同一职级和1，如果第一个模型应该后的第一款车型应该的前一秒，0。

"sortBy" comparator functions take a model and return a numeric or string value by which the model should be ordered relative to others. "sort" comparator functions take two models, and return -1 if the first model should come before the second, 0 if they are of the same rank and 1 if the first model should come after.

因此​​，在这种情况下，我们可以写一个不同比较器功能：

So in this case, we can write a different comparator function:

var Chapter  = Backbone.Model;
var chapters = new Backbone.Collection;

chapters.comparator = function(chapterA, chapterB) {
  if (chapterA.get('title') > chapterB.get('title')) return -1; // before
  if (chapterB.get('title') > chapterA.get('title')) return 1; // after
  return 0; // equal
};

chapters.add(new Chapter({page: 9, title: "The End"}));
chapters.add(new Chapter({page: 5, title: "The Middle"}));
chapters.add(new Chapter({page: 1, title: "The Beginning"}));

alert(chapters.pluck('title'));

所以，你应该得到作为一个响应：

So you should get as a response:

"The Middle", "The End", "The Beginning"

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