轻松使用concat函数:

var a = [1,2,3];
var b = [2,3,4];
a = a.concat(b);
>> [1,2,3,2,3,4]

这样解决。

let arr = [[1, 2], [3, 4], [5, 6]];
 console.log([].concat(...arr));

最快的10倍是迭代数组，就像它们是一个数组一样，而不实际连接它们(如果可以的话)。

我很惊讶concat比push稍微快一点，除非测试不公平。

const arr1 = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i']; const arr2 = ['j', 'k', 'l', 'i', 'm', 'n', 'o', 'p', 'q', 'r', 's']; const arr3 = ['t', 'u', 'v', 'w']; const arr4 = ['x', 'y', 'z']; let start; // Not joining but iterating over all arrays - fastest // at about 0.06ms start = performance.now() const joined = [arr1, arr2, arr3, arr4]; for (let j = 0; j < 1000; j++) { let i = 0; while (joined.length) { // console.log(joined[0][i]); if (i < joined[0].length - 1) i++; else { joined.shift() i = 0; } } } console.log(performance.now() - start); // Concating (0.51ms). start = performance.now() for (let j = 0; j < 1000; j++) { const a = [].concat(arr1, arr2, arr3, arr4); } console.log(performance.now() - start); // Pushing on to an array (mutating). Slowest (0.77ms) start = performance.now() const joined2 = [arr1, arr2, arr3, arr4]; for (let j = 0; j < 1000; j++) { const arr = []; for (let i = 0; i < joined2.length; i++) { Array.prototype.push.apply(arr, joined2[i]) } } console.log(performance.now() - start);

如果你抽象它，你可以让不加入的迭代更干净，它仍然是原来的两倍:

const arr1 = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i']; const arr2 = ['j', 'k', 'l', 'i', 'm', 'n', 'o', 'p', 'q', 'r', 's']; const arr3 = ['t', 'u', 'v', 'w']; const arr4 = ['x', 'y', 'z']; function iterateArrays(arrays, onEach) { let i = 0; while (joined.length) { onEach(joined[0][i]); if (i < joined[0].length - 1) i++; else { joined.shift(); i = 0; } } } // About 0.23ms. let start = performance.now() const joined = [arr1, arr2, arr3, arr4]; for (let j = 0; j < 1000; j++) { iterateArrays(joined, item => { //console.log(item); }); } console.log(performance.now() - start);

concat()方法用于连接两个或多个数组。它不会更改现有数组，只返回已连接数组的副本。

array1 = array1.concat(array2, array3, array4, ..., arrayN);

现在我们可以使用ES6 Spread组合多个数组。 不要使用concat()来连接数组，而是尝试使用spread语法将多个数组组合成一个扁平数组。 例如:

var a = [1,2];
var b = [3,4];
var c = [5,6,7];
var d = [...a, ...b, ...c];
// resulting array will be like d = [1,2,3,4,5,6,7]

用ES6缩短。

new Set([].concat(...Array));

这可以连接并唯一多个数组;

let Array = [ [“vue”,“巴别塔”,“npm”,“杯”,“mysql”,“少”,“laravel”), (“jquery”、“反应”,js, css, wordpress,“html”,“引导”), [“vue”,“巴别塔”,“npm”,“杯”,“mysql”,“少”,“laravel”), (‘角’,‘cms’,‘js’,‘css’,‘graphql’,‘nodejs ', ' php '], (“severless”、“无头”、“js”,“css”,“设计”,“ps”,“php”), ］ const Boom = new Set([].concat(…数组)); //不需要 let dStr = "; Boom.forEach (e = > { dStr += e + ' '; }) document . write(下游); < div class = "结果" > < / div >