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JavaScript

Posted by natalieman
natalieman
328 Points

how to convert items into integer in array with different values

Is it possible to convert items that are numbers into integer but leave those that are not as a string?

For example

From this:

var a = ["1", "2","b","k","blue","100"]

To this:

var a = [1, 2,"b","k","blue",100]

Thanks

3 Answers

Dave McFarland
STAFF
Dave McFarland
Treehouse Teacher
Dave McFarland
Dave McFarland
Treehouse Teacher

Hi Natalie Man

Sure. Here's one simple way:

for (var i = 0; i < a.length; i++ ) {
 if ( ! isNaN(a[i]) ) {
     a[i] = +a[i];
 }   
}

If your array has Boolean values -- true or false -- you'll need to test for those as well, since JavaScript converts those to numbers:

for (var i = 0; i < a.length; i++ ) {
 if ( ! isNaN(a[i]) && typeof a[i] !== 'boolean') {
     a[i] = +a[i];
 }   
}

The + operator is a quick way to convert a string with a number to a number. It works with both integers and floating point values. For example, +'1.4' will become 1.4.

Kang-Kyu Lee
Kang-Kyu Lee
53,143 Points
Kang-Kyu Lee
Kang-Kyu Lee
53,143 Points

Hi Natalie. there should be better solution, but I would use if like this:

isNaN(parseInt(string)) ? string : parseInt(string);

And because this is an array, this could be done:

var array = [1, 2,"b","k","blue",100];
for(i=0; i<array.length; i++) {
  array[i] = isNaN(parseInt(array[i])) ? array[i] : parseInt(array[i]);
}
Kang-Kyu Lee
Kang-Kyu Lee
53,143 Points

Dave's answer came while I was typing, and I didn't consider float number! His should be a better answer definitely :)

natalieman
natalieman
328 Points
natalieman
natalieman
328 Points

Thanks the reply I'll give them a try and see how it goes :)