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

Array.prototype.add = function(b){
    var a = this.concat();                // clone current object
    if(!b.push || !b.length) return a;    // if b is not an array, or empty, then return a unchanged
    if(!a.length) return b.concat();      // if original is empty, return b

    // go through all the elements of b
    for(var i = 0; i < b.length; i++){
        // if b's value is not in a, then add it
        if(a.indexOf(b[i]) == -1) a.push(b[i]);
    }
    return a;
}

// Example:
console.log([1,2,3].add([3, 4, 5])); // will output [1, 2, 3, 4, 5]

其他回答

如果不希望复制特定属性(例如ID)

let noDuplicate = array1.filter ( i => array2.findIndex(a => i.id==a.id)==-1 );
let result = [...noDuplicate, ...array2];

这是我需要合并(或返回两个数组的并集)时使用的函数。

var union = function (a, b) {
  for (var i = 0; i < b.length; i++)
    if (a.indexOf(b[i]) === -1)
      a.push(b[i]);
  return a;
};

var a = [1, 2, 3, 'a', 'b', 'c'];
var b = [2, 3, 4, 'b', 'c', 'd'];

a = union(a, b);
//> [1, 2, 3, "a", "b", "c", 4, "d"]

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

var array3 = union(array1, array2);
//> ["Vijendra", "Singh", "Shakya"]

只需使用Undercore.js的=>uniq即可实现:

array3 = _.uniq(array1.concat(array2))

console.log(array3)

它将印刷[“Vijendra”、“Singh”、“Shakya”]。

这很简单,可以用jQuery在一行中完成:

var arr1 = ['Vijendra', 'Singh'], arr2 =['Singh', 'Shakya'];

$.unique(arr1.concat(arr2))//one line

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

之前写过同样的原因(适用于任意数量的数组):

/**
 * Returns with the union of the given arrays.
 *
 * @param Any amount of arrays to be united.
 * @returns {array} The union array.
 */
function uniteArrays()
{
    var union = [];
    for (var argumentIndex = 0; argumentIndex < arguments.length; argumentIndex++)
    {
        eachArgument = arguments[argumentIndex];
        if (typeof eachArgument !== 'array')
        {
            eachArray = eachArgument;
            for (var index = 0; index < eachArray.length; index++)
            {
                eachValue = eachArray[index];
                if (arrayHasValue(union, eachValue) == false)
                union.push(eachValue);
            }
        }
    }

    return union;
}    

function arrayHasValue(array, value)
{ return array.indexOf(value) != -1; }