解析以2位小数浮点

Question

I need to round a value with 2 decimal places that I receive from a web service. To do this i use this methods toFixed and parseFloat because I need the final value in a float. However when I have this value "5.5000000" he shows me the value with only one decimal place "5.5"...

I did in that way:

var num = 5.5000000;
var n = num.toFixed(2);
var numFinal = parseFloat(n);

Answer 1

您必须在parseFloat之后调用toFixed ：

parseFloat(yourString).toFixed(2)

Answer 2

You can do something like this

   /**
       * Convert the value to the Number with the precision.
       * @param   {Number} value         value to be converted
       * @param   {Number} [precision=0] number of decimal places
       * @returns {Number} converted number.
       */
      function toNumber (value, precision) {
        precision = precision || 0;
        if (precision === 0) {
          return value * 1;
        } else {
          return Number((value * 1).toFixed(precision));
        }
      }

Answer 3

Short Answer : There is no way in JS to have Number datatype value with trailing zeros after a decimal.

Long Answer : Its the property of toFixed or toPrecision function of JavaScript, to return the String. The reason for this is that the Number datatype cannot have value like a = 2.00, it will always remove the trailing zeros after the decimal, This is the inbuilt property of Number Datatype. So to achieve the above in JS we have 2 options

1. Either use data as a string or
2. Agree to have truncated value with case '0' at the end ex 2.50 -> 2.5. Number Cannot have trailing zeros after decimal