如何在 JavaScript 中合并两个数组并删除重复项 [英] How to merge two arrays in JavaScript and de-duplicate items

问题描述

我有两个 JavaScript 数组:

I have two JavaScript arrays:

var array1 = ["Vijendra","Singh"];
var array2 = ["Singh", "Shakya"];

我希望输出为:

var array3 = ["Vijendra","Singh","Shakya"];

输出数组应该删除重复的单词.

The output array should have repeated words removed.

如何在 JavaScript 中合并两个数组，以便仅从每个数组中按照它们插入原始数组的相同顺序获取唯一项?

How do I merge two arrays in JavaScript so that I get only the unique items from each array in the same order they were inserted into the original arrays?

推荐答案

只合并数组(不删除重复项)

To just merge the arrays (without removing duplicates)

var array1 = ["Vijendra", "Singh"];
var array2 = ["Singh", "Shakya"];

console.log(array1.concat(array2));

const array1 = ["Vijendra","Singh"];
const array2 = ["Singh", "Shakya"];
const array3 = [...array1, ...array2];

因为没有内置"的方式来删除重复项(ECMA-262 实际上有 Array.forEach ，这对这个非常有用)，我们必须手动完成:

Since there is no 'built in' way to remove duplicates (ECMA-262 actually has Array.forEach which would be great for this), we have to do it manually:

Array.prototype.unique = function() {
    var a = this.concat();
    for(var i=0; i<a.length; ++i) {
        for(var j=i+1; j<a.length; ++j) {
            if(a[i] === a[j])
                a.splice(j--, 1);
        }
    }

    return a;
};

然后，使用它:

var array1 = ["Vijendra","Singh"];
var array2 = ["Singh", "Shakya"];
// Merges both arrays and gets unique items
var array3 = array1.concat(array2).unique(); 

这也将保留数组的顺序(即不需要排序).

This will also preserve the order of the arrays (i.e, no sorting needed).

由于很多人对 Array.prototype 和 for in 循环的原型增强感到恼火，这里有一种侵入性较小的使用方法:

Since many people are annoyed about prototype augmentation of Array.prototype and for in loops, here is a less invasive way to use it:

function arrayUnique(array) {
    var a = array.concat();
    for(var i=0; i<a.length; ++i) {
        for(var j=i+1; j<a.length; ++j) {
            if(a[i] === a[j])
                a.splice(j--, 1);
        }
    }

    return a;
}

var array1 = ["Vijendra","Singh"];
var array2 = ["Singh", "Shakya"];
    // Merges both arrays and gets unique items
var array3 = arrayUnique(array1.concat(array2));

对于那些有幸使用 ES5 可用的浏览器的人，您可以像这样使用 Object.defineProperty:

For those who are fortunate enough to work with browsers where ES5 is available, you can use Object.defineProperty like this:

Object.defineProperty(Array.prototype, 'unique', {
    enumerable: false,
    configurable: false,
    writable: false,
    value: function() {
        var a = this.concat();
        for(var i=0; i<a.length; ++i) {
            for(var j=i+1; j<a.length; ++j) {
                if(a[i] === a[j])
                    a.splice(j--, 1);
            }
        }

        return a;
    }
});

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