如何将数组切片直到某个元素

Question

我有一个包含字符串和对象的数组。字符串充当“标题”，而跟随它们的对象是“内容”。这样安排是出于虚拟化的目的。这是我到目前为止所得到的

const test = [
    "string 1",
    { prop1: "string 1 obj first" },
    { prop1: "string 1 obj" },
    { prop1: "string 1 obj" },
    { prop1: "string 1 obj" },
    { prop1: "string 1 obj last" },
    "string 2",
    { prop1: "string 2 obj first" },
    { prop1: "string 2 obj" },
    { prop1: "string 2 obj" },
    { prop1: "string 2 obj last" },
    "string 3",
    { prop1: "string 3 obj first" },
    { prop1: "string 3 obj" },
    { prop1: "string 3 obj" },
    { prop1: "string 3 obj" },
    { prop1: "string 3 obj" },
    { prop1: "string 3 obj" },
    { prop1: "string 3 obj last" },
]

const result = test.reduce((acc, curr, i, arr) => {
    const next = arr[i+1]

    // with Title
    if (typeof curr === 'string') {
        if (typeof next === 'object' && next !== null) {
            // get the index for the next title from here
            const nextTitleIndex = test.slice(i + 1).findIndex((item) => typeof item === 'string');
            // slice the array from this point up to the index of the next title (not included)
            const objects = test.slice(i + 1, nextTitleIndex === -1 ? undefined : nextTitleIndex + 1)

            console.log({ nextTitleIndex, objects })
        }
    }

    return acc
}, [])

我需要获取当前迭代的标题和沿线的下一个标题之间的所有对象。 （示例中为“字符串1”和“字符串2”之间的对象等）

第一次和最后一次迭代按预期工作，

objects

变量包含从

first

到

last

的五/七个对象。然而，中间的迭代不会产生

objects

所需的值，它变成一个空数组。

Answer 1

您没有指定最终结果应该是什么，所以我为您挑选两个：

数组的数组，数组的第一个元素是标题：

const result = [];
test.forEach((s) => {
  if(typeof s === 'string') {
    result.push([]);
  }
  result[result.length - 1].push(s); // access error when the test data is not structured correctly
});

console.log(result); // [['string 1', { prop1: "string 1 obj first" }, ...],['string 2', ...], ...]

一个对象，其键是标题，值是内容对象的数组：

const result = {};
let key = undefined;
test.forEach((s) => {
  if(typeof s === 'string') {
    key = s;
    result[key] = [];
  } else {
    result[key].push(s); // semantic error when the test data is not structured correctly
  }  
});

console.log(result); // {string 1: [{ prop1: "string 1 obj first" }, ...], string 2: [...], ...}