移动逗号 position JavaScript

Question

I'm trying to move the position of the comma with the use of JavaScript. I have managed to remove all the parts of the string I needed removing. The only problem is that the comma is in the wrong position.

The current outcome is 425.00 , but I simply want '42.50'

success: function(result) {
   if (result != '') {
      alert(" "+result+" ");
   }

   var discountVal = result.replace(/\D/g,'');
   newDiscountVal = discountVal.replace(7.50, '');
   $("input#amount").val(discountVal);
}

I am grabbing database echo values with a combination of string and echo - numbers..

Answer 1

If it is number you can just divide by 10

If it is string you can do like this:

var ind = text.indexOf('.');
text = text.replace('.', '');
text.slice(0, ind-1) + '.' + text.slice(ind-1, text.length)

Answer 2

You could divide by ten, then convert back to a String using toFixed(2) which forces formatting of 2 decimal places

Javascript allows implicit conversion of Strings to numbers, by firstly converting the String to a Number so it is valid to divide a String by a number.

var input= "4250.00";
var output = (original / 100).toFixed(2); // => "42.50" 

Note this method has different behaviour due to rounding. Consider the case 9.99. If you use a string manipulation technique you'll get ".99", with divide by 10 method above you'll get "1.00". However from what has been said in comments I believe your inputs always end .00 and never anything else, so there will be no difference in reality.

Answer 3

Here is a solution:

function moveComma(val, moveCommaByInput) {
  if (val || typeof val === 'number') {
    const valueNumber = Number(val);
    const moveCommaBy = moveCommaByInput || 0;

    if (isNaN(valueNumber)) {
      return null;
    } else {
      return Number(`${valueNumber}e${moveCommaBy}`);
    }
  }

  return null;
}

Answer 4

This is how i solved it..

                      var discountVal = result.replace(/\D/g, '');
                      var newDiscountVal = discountVal.replace(7.50, '');
                      var lastDigits = newDiscountVal.substr(newDiscountVal.length - 2);
                      var removedDigits = newDiscountVal.slice(0,newDiscountVal.length - 2);
                      var discountRealValue = removedDigits + '.' + lastDigits;
                      $("input#amount").val(discountRealValue);

Cheers