我有两个JavaScript数组:

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

我希望输出为:

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

输出数组应删除重复的单词。

如何在JavaScript中合并两个数组,以便从每个数组中只获得唯一的项目,其顺序与它们插入原始数组的顺序相同?


当前回答

我简化了这个答案的最佳部分,并将其转化为一个很好的函数:

function mergeUnique(arr1, arr2){
    return arr1.concat(arr2.filter(function (item) {
        return arr1.indexOf(item) === -1;
    }));
}

其他回答

新解决方案(使用Array.prototype.indexOf和Array.prototype.cocat):

Array.prototype.uniqueMerge = function( a ) {
    for ( var nonDuplicates = [], i = 0, l = a.length; i<l; ++i ) {
        if ( this.indexOf( a[i] ) === -1 ) {
            nonDuplicates.push( a[i] );
        }
    }
    return this.concat( nonDuplicates )
};

用法:

>>> ['Vijendra', 'Singh'].uniqueMerge(['Singh', 'Shakya'])
["Vijendra", "Singh", "Shakya"]

Array.prototype.indexOf(用于internet explorer):

Array.prototype.indexOf = Array.prototype.indexOf || function(elt)
  {
    var len = this.length >>> 0;

    var from = Number(arguments[1]) || 0;
    from = (from < 0) ? Math.ceil(from): Math.floor(from); 
    if (from < 0)from += len;

    for (; from < len; from++)
    {
      if (from in this && this[from] === elt)return from;
    }
    return -1;
  };

/***对仅保留唯一值的数组进行重复数据消除。*使用哈希表(js对象)过滤重复项。*保持数组元素的顺序。*该算法对于大型阵列(线性时间)特别有效。*/函数数组UniqueFast(arr){var seen={};var结果=[];变量i,长度=arr.length;对于(i=0;i<len;i++){var项目=arr[i];//哈希表查找if(!seed[item]){result.push(项);seed[项目]=真;}}返回结果;}/////测试var array1=[“Vijendra”,“Singh”];var array2=[“Singh”,“Shakya”];var result=arrayUniqueFast(array1.concat(array2));document.write('<br>result:'+result);

有关阵列重复数据消除的其他方法,请参阅我的基准测试:https://jsperf.com/de-duplicate-an-array-keeping-only-unique-values

您可以合并结果并过滤重复项:

let combinedItems = [];

// items is an Array of arrays: [[1,2,3],[1,5,6],...]    
items.forEach(currItems => {
    if (currItems && currItems.length > 0) {
        combinedItems = combinedItems.concat(currItems);
    }
});

let noDuplicateItems = combinedItems.filter((item, index) => {
    return !combinedItems.includes(item, index + 1);
});

为此……这里有一个单行解决方案:

const x = [...new Set([['C', 'B'],['B', 'A']].reduce( (a, e) => a.concat(e), []))].sort()
// ['A', 'B', 'C']

不是特别可读,但它可能会帮助某人:

将初始累加器值设置为空数组的reduce函数应用于空数组。reduce函数使用concat将每个子数组附加到累加器数组上。其结果作为构造函数参数传递,以创建新的Set。排列运算符用于将集合转换为数组。sort()函数应用于新数组。

我有一个类似的请求,但它具有数组中元素的Id。

这里是我进行重复数据消除的方法。

它简单,易于维护,使用方便。

// Vijendra's Id = Id_0
// Singh's Id = Id_1
// Shakya's Id = Id_2

let item0 = { 'Id': 'Id_0', 'value': 'Vijendra' };
let item1 = { 'Id': 'Id_1', 'value': 'Singh' };
let item2 = { 'Id': 'Id_2', 'value': 'Shakya' };

let array = [];

array = [ item0, item1, item1, item2 ];

let obj = {};
array.forEach(item => {
    obj[item.Id] = item;
});

let deduplicatedArray = [];
let deduplicatedArrayOnlyValues = [];
for(let [index, item] of Object.values(obj).entries()){
    deduplicatedArray = [ ...deduplicatedArray, item ];
    deduplicatedArrayOnlyValues = [ ...deduplicatedArrayOnlyValues , item.value ];
};
    
console.log( JSON.stringify(array) );
console.log( JSON.stringify(deduplicatedArray) );
console.log( JSON.stringify(deduplicatedArrayOnlyValues ) );

控制台日志

[{"recordId":"Id_0","value":"Vijendra"},{"recordId":"Id_1","value":"Singh"},{"recordId":"Id_1","value":"Singh"},{"recordId":"Id_2","value":"Shakya"}]

[{"recordId":"Id_0","value":"Vijendra"},{"recordId":"Id_1","value":"Singh"},{"recordId":"Id_2","value":"Shakya"}]

["Vijendra","Singh","Shakya"]