Lodash - 如何对数组的数组长度求和

Question

我有一个数组数组

const myArrays = [
    [ 1, 2, 3, 4], // length = 4
    [ 1, 2], // length = 2
    [ 1, 2, 3], // length = 3
];

如何获取所有子数组的总长度？

const length = 4 + 2 + 3

Answer 1

你可以使用_.sumBy

const myArrays = [
    [ 1, 2, 3, 4], // length = 4
    [ 1, 2], // length = 2
    [ 1, 2, 3], // length = 3
];

 var length = _.sumBy(myArrays, 'length');
console.log("length =", length);

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