如何在敲除映射中使用 ko.toJs 方法而无需计算属性? [英] How can I use ko.toJs method without computed properties in knockout mapping?

问题描述

我想将 viewModel 转换为 Json 对象.但我不想映射计算属性.

I want to convert viewModel to Json object. But I don't want to map computed properties.

推荐答案

如果您要将其转换为 JSON，这里有几个选项:

Here are a few options, if you are going to convert it to JSON:

1. 如果您为对象使用构造函数，则可以覆盖 .toJSON 函数来控制要输出的属性.这是一篇关于它的文章:http://www.knockmeout.net/2011/04/controlling-how-object-is-converted-to.html.这是一个示例:http://jsfiddle.net/rniemeyer/FE4HX/.

1. if you are using constructor functions for your object, then you can override the .toJSON function to control which properties to output. Here is an article on it: http://www.knockmeout.net/2011/04/controlling-how-object-is-converted-to.html. Here is a sample: http://jsfiddle.net/rniemeyer/FE4HX/.

在 KO 2.1 中，当使用 ko.toJSON 时，第二个和第三个参数现在被传递给 JSON.stringify.以下是有关参数的一些文档:https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/JSON/stringify.这意味着您可以使用要包含的属性数组或处理键/值的函数传递第二个参数 (replacer).以下是使用此技术的相同示例:http://jsfiddle.net/rniemeyer/huyLe/.

in KO 2.1, when using ko.toJSON the second and third arguments are now passed to JSON.stringify. Here is some documentation on the arguments: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/JSON/stringify. This means that you can pass the second argument (replacer) with either an array of properties to include or a function that processes the key/values. Here is the same sample using this technique: http://jsfiddle.net/rniemeyer/huyLe/.

我经常使用的另一个选项是将您不希望在 JSON 输出中的计算定义为子可观察对象.Observables 是函数，它们是对象，因此您实际上可以在 observables 上定义 observables.喜欢:

Another option that I use frequently, is to define computeds that you don't want in your JSON output as sub-observables. Observables are functions, which are objects, so you can actually define observables on observables. Like:

-

this.name = ko.observable("Bob");
this.name.formatted = ko.computed(...);

现在当转换为 JSON 时，formatted 自然会丢失，因为 name 被转换为它的值.下面是相同的示例:http://jsfiddle.net/rniemeyer/peEGG/.通常我在它是关于可观察的元数据时使用它(isValid、isEditing 等).

Now when converting to JSON, formatted will be naturally lost as name gets converted to its value. Here is the same sample again: http://jsfiddle.net/rniemeyer/peEGG/. Usually I use this when it is meta-data about an observable (isValid, isEditing, etc.).

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