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
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
var a = [1,2,3]
var b = [1,2,4,5]
我喜欢一行。这将把不同的b元素推到
b.forEach(item => a.includes(item) ? null : a.push(item));
另一个版本不会修改
var c = a.slice();
b.forEach(item => c.includes(item) ? null : c.push(item));
我学会了一种用扩展运算符连接两个数组的小方法:
var array1 = ['tom', 'dick', 'harry'];
var array2 = ['martin', 'ricky'];
array1.push(...array2);
“…”扩展运算符将以下数组拆分为单个项,然后push可以将它们作为单独的参数处理。
给定两个没有重复的简单类型的排序数组,这将在O(n)时间内合并它们,并且输出也将被排序。
function merge(a, b) {
let i=0;
let j=0;
let c = [];
for (;;) {
if (i == a.length) {
if (j == b.length) return c;
c.push(b[j++]);
} else if (j == b.length || a[i] < b[j]) {
c.push(a[i++]);
} else {
if (a[i] == b[j]) ++i; // skip duplicates
c.push(b[j++]);
}
}
}
模块化,通用
这可以通过组成两个基本功能来实现。
const getUniqueMerge = (...arrs) => getUniqueArr(mergeArrs(...arrs))
const getUniqueArr = (array) => Array.from(new Set(array))
const mergeArrs = (...arrs) => [].concat(...arrs)
它可以处理无限的数组或值
console.log(getUniqueMerge(["Vijendra","Singh"],["Singh", "Shakya"])
// ["Vijendra", "Singh", "Shakya"]
console.log(getUniqueMerge(["Sheldon", "Cooper"], ["and", "Cooper", "Amy", "and"], "Farrah", "Amy", "Fowler"))
// ["Sheldon", "Cooper", "and", "Amy", "Farrah", "Fowler"]
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);
});