ES6传播功能#ohmy #ftw

Const chunk = (size, xs) => xs.reduce ( (segments， _， index) => 索引%大小=== 0 ？ […段,x。Slice (index, index + size)] 段, ［］ ）; console.log(块(3,(1,2,3,4,5,6,7,8)));

如果你使用EcmaScript >= 5.1版本，你可以使用array.reduce()实现一个函数版本的chunk()，复杂度为O(N):

function chunk(chunkSize, array) { return array.reduce(function(previous, current) { var chunk; if (previous.length === 0 || previous[previous.length -1].length === chunkSize) { chunk = []; // 1 previous.push(chunk); // 2 } else { chunk = previous[previous.length -1]; // 3 } chunk.push(current); // 4 return previous; // 5 }, []); // 6 } console.log(chunk(2, ['a', 'b', 'c', 'd', 'e'])); // prints [ [ 'a', 'b' ], [ 'c', 'd' ], [ 'e' ] ]

以上每个// nbr的解释:

如果之前的值，即之前返回的块数组是空的，或者如果之前的最后一个块有chunkSize项，则创建一个新的块 将新数据块添加到现有数据块数组中 否则，当前块是块数组中的最后一个块 将当前值添加到块中 返回修改后的块数组 通过传递一个空数组初始化还原

基于chunkSize的curry:

var chunk3 = function(array) {
    return chunk(3, array);
};

console.log(chunk3(['a', 'b', 'c', 'd', 'e']));
// prints [ [ 'a', 'b', 'c' ], [ 'd', 'e' ] ]

你可以将chunk()函数添加到全局Array对象:

Object.defineProperty(Array.prototype, 'chunk', { value: function(chunkSize) { return this.reduce(function(previous, current) { var chunk; if (previous.length === 0 || previous[previous.length -1].length === chunkSize) { chunk = []; previous.push(chunk); } else { chunk = previous[previous.length -1]; } chunk.push(current); return previous; }, []); } }); console.log(['a', 'b', 'c', 'd', 'e'].chunk(4)); // prints [ [ 'a', 'b', 'c' 'd' ], [ 'e' ] ]

如果这对任何人都有用，这可以在RxJS 6中非常简单地完成:

const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16];
from(arr).pipe(bufferCount(3)).subscribe(chunk => console.log(chunk));

输出:[1,2,3](4、5、6)[7 8 9](10、11、12)(13、14、15)[16]

我的技巧是使用parseInt(i/chunkSize)和parseInt(i%chunkSize)，然后填充数组

// filling items let array = []; for(let i = 0; i< 543; i++) array.push(i); // printing the splitted array console.log(getSplittedArray(array, 50)); // get the splitted array function getSplittedArray(array, chunkSize){ let chunkedArray = []; for(let i = 0; i<array.length; i++){ try{ chunkedArray[parseInt(i/chunkSize)][parseInt(i%chunkSize)] = array[i]; }catch(e){ chunkedArray[parseInt(i/chunkSize)] = []; chunkedArray[parseInt(i/chunkSize)][parseInt(i%chunkSize)] = array[i]; } } return chunkedArray; }

Const array = ['a'， 'b'， 'c'， 'd'， 'e']; Const size = 2; Const chunks = []; While (array.length) { chunks.push(数组。拼接(0,大小)); ｝ console.log(块);

一个有效的解决方案是通过indexChunk将解决方案与slice和push连接起来，解决方案被分割成块:

function splitChunks(sourceArray, chunkSize) { if(chunkSize <= 0) throw "chunkSize must be greater than 0"; let result = []; for (var i = 0; i < sourceArray.length; i += chunkSize) { result[i / chunkSize] = sourceArray.slice(i, i + chunkSize); } return result; } let ar1 = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 ]; console.log("Split in chunks with 4 size", splitChunks(ar1, 4)); console.log("Split in chunks with 7 size", splitChunks(ar1, 7));