使用include的Javascript过滤器对象 [英] Javascript filter object using includes

问题描述

我正在尝试使用javascript中的filter()函数过滤对象.

I'm trying to filter an object using the filter() function in javascript .

我想再次过滤这样的数组:[1615，1616].在代码中将其称为value.verdier.

I want to filter againts an array like this: [1615, 1616]. It's referenced in the code as value.verdier.

数据集是一个大型数组，其中包含具有多个属性的对象，这些属性是通过JSON字符串解析的.数组中的每个对象都有一个名为kat_id的属性.

Dataset is a large array holding objects that have several properties, parsed from a JSON string. Each object in the array has a property named kat_id.

目标是减少数组，使其仅容纳kat_id = 1615或kat_id = 1616的对象.或我在value.verdier中具有的其他任何值.

The goal is to reduce the array so that it only holds objects where kat_id=1615 or kat_id=1616. Or any other value that I have in value.verdier.

我的代码是这样的:

dataset = dataset.filter(function (el) 
     {
        return value.verdier.includes(el.kat_id );
     });

我可能错过了一些非常明显的东西.

I'm problably missing something really obvious.

推荐答案

目标是减少数组，使其仅容纳kat_id = 1615或kat_id = 1616的对象.或 value.verdier 中的其他任何值.

如果值和 value.verdier 中的值都是数字或全部 strings .这是因为 includes 在传递给它的东西和调用它的数组中的条目之间进行了 === .因此 [1、2、3] .includes("2")是 false ， ["1"，"2"，"3"].includes(2).

The code in your question will do that, if the kat_id values and the values in value.verdier are all numbers or all strings. That's because includes does a === between the thing you pass into it and the entries in the array you call it on. So [1, 2, 3].includes("2") is false, as is ["1", "2", "3"].includes(2).

不过，我假设您不会发布该问题是否有效，所以我假设 kat_id 的值类型和 value.verdier的值类型.是不同的 —其中一个是数字，另一个是字符串.

I assume you wouldn't be posting the question if it were working, though, so I assume the type of the values of kat_id and the type of the values in value.verdier are different — one of them is a number, the other is a string.

如果 kat_id 值为字符串，而 value.verdier 值为数字，则需要解析 kat_id 编号，然后再使用 includes :

If the kat_id values are strings and the value.verdier values are numbers, you need to parse kat_id to number before using includes:

return value.verdier.includes(parseInt(el.kat_id, 10));

实时示例:

var value = {
    verdier: [1615, 1616]
};

var dataset = [
    {kat_id: "1", expected: "omit"},
    {kat_id: "2", expected: "omit"},
    {kat_id: "1615", expected: "retain"},
    {kat_id: "3", expected: "omit"},
    {kat_id: "1616", expected: "retain"},
    {kat_id: "4", expected: "omit"},
    {kat_id: "5", expected: "omit"},
];
dataset = dataset.filter(function (el) 
{
    return value.verdier.includes(parseInt(el.kat_id, 10));
});
console.log(dataset);

或者，如果 kat_id 的值是数字，而 value.verdier 的值是字符串，则需要先将 kat_id 的数字转换成字符串使用 includes :

Or if the kat_id values are numbers and the value.verdier values are strings, you need to convert the kat_id numbers to strings before using includes:

return value.verdier.includes(String(el.kat_id));

实时示例:

var value = {
    verdier: ["1615", "1616"]
};

var dataset = [
    {kat_id: 1, expected: "omit"},
    {kat_id: 2, expected: "omit"},
    {kat_id: 1615, expected: "retain"},
    {kat_id: 3, expected: "omit"},
    {kat_id: 1616, expected: "retain"},
    {kat_id: 4, expected: "omit"},
    {kat_id: 5, expected: "omit"},
];
dataset = dataset.filter(function (el) 
{
    return value.verdier.includes(String(el.kat_id));
});
console.log(dataset);

如果值 vary (某些 kat_id 是字符串，另一些是数字，和/或某些 value.verdier 值是字符串和其他是数字)，则可能需要 some ，而不是 includes 和类型不敏感的比较:

If the values vary (some kat_ids are strings and others are numbers, and/or some value.verdier values are strings and others are numbers), you probably need some rather than includes and a type-insensitive comparison:

return value.verdier.some(function(val) { return String(val) === String(el.kat_id); });

实时示例:

var value = {
    verdier: [1615, "1616"]
};

var dataset = [
    {kat_id: "1", expected: "omit"},
    {kat_id: 2, expected: "omit"},
    {kat_id: "1615", expected: "retain"},
    {kat_id: "3", expected: "omit"},
    {kat_id: 1616, expected: "retain"},
    {kat_id: "4", expected: "omit"},
    {kat_id: 5, expected: "omit"},
];
dataset = dataset.filter(function (el) 
{
    return value.verdier.some(function(val) { return String(val) === String(el.kat_id); });
});
console.log(dataset);

我在上面坚持使用ES5级代码，因为您的问题似乎只在使用ES5级代码.但是以下是使用ES2015 +的示例:

I've stuck with ES5-level code above because your question seemed to be using ES5-level code only. But here are those examples using ES2015+:

dataset = dataset.filter(el => value.verdier.includes(parseInt(el.kat_id, 10)));

const value = {
    verdier: [1615, 1616]
};

let dataset = [
    {kat_id: "1", expected: "omit"},
    {kat_id: "2", expected: "omit"},
    {kat_id: "1615", expected: "retain"},
    {kat_id: "3", expected: "omit"},
    {kat_id: "1616", expected: "retain"},
    {kat_id: "4", expected: "omit"},
    {kat_id: "5", expected: "omit"},
];
dataset = dataset.filter(el => value.verdier.includes(parseInt(el.kat_id, 10)));
console.log(dataset);

dataset = dataset.filter(el => value.verdier.includes(String(el.kat_id)));

const value = {
    verdier: ["1615", "1616"]
};

let dataset = [
    {kat_id: 1, expected: "omit"},
    {kat_id: 2, expected: "omit"},
    {kat_id: 1615, expected: "retain"},
    {kat_id: 3, expected: "omit"},
    {kat_id: 1616, expected: "retain"},
    {kat_id: 4, expected: "omit"},
    {kat_id: 5, expected: "omit"},
];
dataset = dataset.filter(el => value.verdier.includes(String(el.kat_id)));
console.log(dataset);

dataset = dataset.filter(el => value.verdier.some(val => String(val) === String(el.kat_id)));

const value = {
    verdier: [1615, "1616"]
};

let dataset = [
    {kat_id: "1", expected: "omit"},
    {kat_id: 2, expected: "omit"},
    {kat_id: "1615", expected: "retain"},
    {kat_id: "3", expected: "omit"},
    {kat_id: 1616, expected: "retain"},
    {kat_id: "4", expected: "omit"},
    {kat_id: 5, expected: "omit"},
];
dataset = dataset.filter(el => value.verdier.some(val => String(val) === String(el.kat_id)));
console.log(dataset);

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