In my local storage I have some score value stored in array
var obj = localStorage.getItem("scoreList")
output
[0,10,10,0,10]
I want sum of this value like and return to data value
sum = 30
I have tried to convert into string value
var string = JSON.stringify(obj);
output "[0,10,10,0,10]"
How can I execute this sum value ?
[0,10,10,0,10].reduce((sum, a) => sum + a, 0);
localStorage.getItem("scoreList").replace(/(\[|\])/g, '').split(",").map(x => parseFloat(x)).reduce((a,b) => a+b, 0)
a simple way:
JSON.parse(localStorage.getItem("scoreList")).reduce((x, y) => x + y)
If you set the scoreList value as an array, that is:
localStorage.setItem('scoreList', [0,10,10,0,10])
When you get it back it will still be a string, so there's no need for any other kind of validation or data type transformation as you did with JSON.stringfy. The following shoud be enough:
const obj = localStorage.getItem("scoreList")
const total = obj.reduce((sum, item) => sum + item, 0);
//total = 30