Question

我有一个简单的数字数组（对于我的应用程序，它代表用户ID）。例如...

[1, 2, 3]

我还有一个对象数组，例如

[
    {Id: 1, FirstName: "Bob", LastName: "Jones", EmailAddress: "bob@bob.com"},
    {Id: 2, FirstName: "Tessa", LastName: "Wong", EmailAddress: "tes@wong.com"},
    {Id: 3, FirstName: "Craig", LastName: "Murray", EmailAddress: "Craig@muz.com"},
    {Id: 4, FirstName: "Bryce", LastName: "Willamson", EmailAddress: "email@me.com"},
    {Id: 5, FirstName: "Tony", LastName: "Ocka", EmailAddress: "toni@oz.com"}
]

我需要做的是用第二个对象数组中的键Id匹配出现在初始数组中的所有值（并返回一个仅包含匹配项的新对象完整数组）。例如，在这种情况下，我要寻找的结果是：

[
    {Id: 1, FirstName: "Bob", LastName: "Jones", EmailAddress: "bob@bob.com"},
    {Id: 2, FirstName: "Tessa", LastName: "Wong", EmailAddress: "tes@wong.com"},
    {Id: 3, FirstName: "Craig", LastName: "Murray", EmailAddress: "Craig@muz.com"},
]

任何帮助将不胜感激。

Answer 1

在OP中显示您的尝试总是很有帮助的，以帮助其他用户了解您的处境。

您可以为此使用“ Array.filter”和“ includes”。

let arr1 = [1,2,3]

let arr2 = [
    {Id: 1, FirstName: "Bob", LastName: "Jones", EmailAddress: "bob@bob.com"},
    {Id: 2, FirstName: "Tessa", LastName: "Wong", EmailAddress: "tes@wong.com"},
    {Id: 3, FirstName: "Craig", LastName: "Murray", EmailAddress: "Craig@muz.com"},
    {Id: 4, FirstName: "Bryce", LastName: "Willamson", EmailAddress: "email@me.com"},
    {Id: 5, FirstName: "Tony", LastName: "Ocka", EmailAddress: "toni@oz.com"}
]

let result = arr2.filter(d => arr1.includes(d.Id))

console.log(result)

Answer 2

您也可以通过遍历第二个数组来实现此目的

let arr1 = [1,2,3];

let arr2 = [
    {Id: 1, FirstName: "Bob", LastName: "Jones", EmailAddress: "bob@bob.com"},
    {Id: 2, FirstName: "Tessa", LastName: "Wong", EmailAddress: "tes@wong.com"},
    {Id: 3, FirstName: "Craig", LastName: "Murray", EmailAddress: "Craig@muz.com"},
    {Id: 4, FirstName: "Bryce", LastName: "Willamson", EmailAddress: "email@me.com"},
    {Id: 5, FirstName: "Tony", LastName: "Ocka", EmailAddress: "toni@oz.com"}
]

let result = [];
for(let i in arr2) {
    if(arr1.indexOf(arr2[i].Id)!==-1) result.push(arr2[i]);
}

console.log(result);

Answer 3

您可以使用Set来优化性能。数组的查找操作花费O(n)，这将使函数的整体时间复杂度增加到O（n ^ 2），而Set中的查找操作花费了O(1)，因此整体时间复杂度为O（ n）。

let arr1 = [1,2,3]

let set = new Set(arr1);

let arr2 = [ {Id: 1, FirstName: "Bob", LastName: "Jones", EmailAddress: "bob@bob.com"}, {Id: 2, FirstName: "Tessa", LastName: "Wong", EmailAddress: "tes@wong.com"}, {Id: 3, FirstName: "Craig", LastName: "Murray", EmailAddress: "Craig@muz.com"}, {Id: 4, FirstName: "Bryce", LastName: "Willamson", EmailAddress: "email@me.com"}, {Id: 5, FirstName: "Tony", LastName: "Ocka", EmailAddress: "toni@oz.com"}];

let result = arr2.filter(({Id}) => set.has(Id))

console.log(result)

如何使用JavaScript根据另一个数组值过滤对象数组？

3 个答案: