I have date duration values in following format.

array1 = '[["2022-01-18","2022-01-21"],["2022-02-15","2022-02-17"], ...]';

And need to convert it as follows,

array2 = [ '2022-01-18 - 2022-01-21', '2022-02-15 - 2022-02-17', ... ]

For the work done I have followed two ways,

1. formattedArray1 = array1.replace(/","/g, " - ").reduce((a, b) => a.concat(b), [])

this gives me an error:

array2.reduce is not a function

2. formattedArray2 = [].concat.apply([], array1.replace(/","/g, " - ")); and this gives me the error

CreateListFromArrayLike called on non-object

To fix this any thought would be highly appreciated!

CodePudding user response：

What you've got there is an array serialised to JSON.

You can

CodePudding user response：

array1 is stored as String, so you need to convert it to Array to use reduce or other array methods.

array1 = '[["2022-01-18","2022-01-21"],["2022-02-15","2022-02-17"]]';
arr = JSON.parse(array1)
formattedArray1 = arr.map((e) => e.join(" - "))
// ['2022-01-18 - 2022-01-21', '2022-02-15 - 2022-02-17']

CodePudding user response：

1. You are calling reduce on type string( array1.replace(/","/g, " - ") will return a string) , reduce works only with Array.prototype that's why you are getting reduce is not a function.

array2.reduce is not a function error.

You need to parse the array before doing reduce.

const array1 = '[["2022-01-18","2022-01-21"],["2022-02-15","2022-02-17"]]';
const parsedArr = JSON.parse(array1);
const result = parsedArr.map(date => date.join(" - ") )
console.log(result)

CodePudding user response：

Another Alternative

The transform could also be done at the same time the json is parsed by providing a reviver function that evaluates each key-value. if the value is a child array then join the elements.

let json = '[["2022-01-18","2022-01-21"],["2022-02-15","2022-02-17"]]';


let data = JSON.parse(json, (k,v) => k && v.push ? v.join(" - ") : v );


console.log(data);