How to find the sum of variables in javascript?

Question

var pagenumber = localStorage["pageno"];
var sum = pagenumber + i;
display(sum);

In this case i am getting the output sum = 11 (when input pagenumber = 1 and i = 1) , But i require the output sum = 2

Both values (or the first) aren't numbers but strings. 1 + 1 = 2 and '1' + '1' = '11'. Use parseInt(localStorage["pageno"]) to parse it. — H. Pauwelyn
– H. Pauwelyn, Commented Feb 1, 2018 at 17:04

Kyle · Accepted Answer · 2018-02-01 17:04:27Z

2

Need to parse the "1" in localStorage to an integer using the built in parseInt funtion:

var pagenumber = localStorage["pageno"];
var sum = Number.parseInt(pagenumber) + i;
display(sum);

answered Feb 1, 2018 at 17:04

Kyle

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Comments

Sebastian Simon · Accepted Answer · 2018-02-01 17:09:56Z

0

You can use parseInt to convert your strings to integers in JavaScript:

var sum = parseInt(localStorage["pageno"]) + parseInt(i);
display(sum);

Sebastian Simon

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answered Feb 1, 2018 at 17:04

IamCavic

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