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?
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
如果像我一样,您需要支持较旧的浏览器,这适用于IE6+
function es3Merge(a, b) {
var hash = {},
i = (a = a.slice(0)).length,
e;
while (i--) {
hash[a[i]] = 1;
}
for (i = 0; i < b.length; i++) {
hash[e = b[i]] || a.push(e);
}
return a;
};
http://jsperf.com/merge-two-arrays-keeping-only-unique-values/22
其他回答
const array3 = array1.filter(t=> !array2.includes(t)).concat(array2)
使用集合(ECMAScript 2015),将非常简单:
const array1=[“Vijendra”,“Singh”];const array2=[“Singh”,“Shakya”];console.log(Array.from(new Set(array1.concat(array2))));
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;
}));
}
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"]
ES6提供了一种单线解决方案,通过使用析构函数和集合来合并多个数组而不重复。
const array1 = ['a','b','c'];
const array2 = ['c','c','d','e'];
const array3 = [...new Set([...array1,...array2])];
console.log(array3); // ["a", "b", "c", "d", "e"]