Merge/flatten an array of arrays
arrays, flatten, javascript, merge, multidimensional-array
Solution
ES2019
ES2019 introduced the `Array.prototype.flat()` method which you could use to flatten the arrays. It is compatible with most environments, although it is only available in Node.js starting with version 11, and not at all in Internet Explorer.
const arrays = [
["$6"],
["$12"],
["$25"],
["$25"],
["$18"],
["$22"],
["$10"]
];
const merge3 = arrays.flat(1); //The depth level specifying how deep a nested array structure should be flattened. Defaults to 1.
console.log(merge3);
Older browsers
For older browsers, you can use `Array.prototype.concat` to merge arrays:
var arrays = [
["$6"],
["$12"],
["$25"],
["$25"],
["$18"],
["$22"],
["$10"]
];
var merged = [].concat.apply([], arrays);
console.log(merged);
Using the `apply` method of `concat` will just take the second parameter as an array, so the last line is identical to this:
var merged = [].concat(["$6"], ["$12"], ["$25"], ["$25"], ["$18"], ["$22"], ["$10"]);
Problem
I have a JavaScript array like: ``` [["$6"], ["$12"], ["$25"], ["$25"], ["$18"], ["$22"], ["$10"]] ``` How would I go about merging the separate inner arrays into one like: ``` ["$6", "$12", "$25", ...] ```