在 JavaScript 中将 2D 嵌套数组转换为 1D 数组？

Question

Given a 2D array as shown in the example, how to manage to combine the string digits into one.

ex: Array2 = [[1,2,3],[4,5,6],[7,8,9]];

required sol:

Array1 = [123, 245, 789];

Answer 1

You can deconstruct your task into two separate problems, that we will solve in turn.

1. We need to take an array of numbers (eg [1, 2,3]) and join them together into a string (eg '123').

There is, in fact, a dedicated function for this in JavaScript - the join() function:

[1, 2, 3].join(''); // '123'

2. We need to perform the previous function on each object in an array, returning an array of the transformed objects.

JavaScript again has you covered, this time with the map() function:

[a, b, c].map((element) => foo(element)); // [foo(a), foo(b), foo(c)]

All we have to do now is join these too together, so that the operation we perform on each element of the parent array, is to join all of the child elements together:

[[1, 2, 3], [4, 5, 6], [7, 8, 9]].map((array) => array.join('')); // ['123', '456', '789']

Answer 2

 function foo(arr){ let toReturn = []; for(let i = 0;i < arr.length;i++){ toReturn.push(arr[i].join("")); } return(toReturn); } console.log(foo([[1,2,3],[4,5,6],[7,8,9]]));

Answer 3

You can use reduce to aggregate your data combined with .join('') to get all element items of each array item into a single value like below:

 const data = [[1,2,3],[4,5,6],[7,8,9]]; const result = data.reduce((acc, curr) => { acc.push(curr.join('')); return acc; }, []); console.log(result);

Answer 4

Return all files as a 1D array from given path

const fetchAllFilesFromGivenFolder = (fullPath) => {
  let files = [];

  fs.readdirSync(fullPath).forEach(file => {
    const absolutePath = path.join(fullPath, file);
    if (fs.statSync(absolutePath).isDirectory()) {
      const filesFromNestedFolder = fetchAllFilesFromGivenFolder(absolutePath);
      filesFromNestedFolder.forEach(file => {
        files.push(file);
      })
    }
    else return files.push(absolutePath);
  });

  return files
}