将数字并排放置的更好方法。 Javascript

Question

I was wondering if there was a better approach to putting 2 numbers side by side without having to make them into a string.

For example:

if i have '2' and '3' and I wanted to '23' you would just concat them. But what if they were the number data type.

I was working with binaries and realized I don't actually know anyway to have

0101, and 1010 and put them together to create 01011010 without turning them into strings.

I know it's an odd question but I am just curious. Thanks again.

Answer 1

Here's a method of doing it without string concatenation:

var values = [2,3];//Also works with arbitrary length arrays, e.g. [1,2,3,4,5]

var result = 0;
for (var i = 0; i < values.length; ++i) {
  var step = values[i] * (Math.pow(10, values.length - i) / 10);
  result += step;
}

https://jsfiddle.net/ysd6exvw/

I've haven't benchmarked it for speed, and TBH I would suggest just using string concatenation instead of complicating the problem with this code.

EDIT:

Added a benchmark:

https://jsfiddle.net/4ap82rgq/

This shows that the string concatenation is fastest, although I did get one result where the above code was faster.