How to parse float with two decimal places in javascript?

Question

I have the following code. I would like to have it such that if price_result equals an integer, let's say 10, then I would like to add two decimal places. So 10 would be 10.00. Or if it equals 10.6 would be 10.60. Not sure how to do this.

price_result = parseFloat(test_var.split('$')[1].slice(0,-1));

Answer 1

If you need performance (like in games):

Math.round(number * 100) / 100

It's about 100 times as fast as parseFloat(number.toFixed(2))

http://jsperf.com/parsefloat-tofixed-vs-math-round

EDIT:

https://jsperf.app/kowulu

Answer 2

parseFloat(parseFloat(amount).toFixed(2))

You have to parse it twice. The first time is to convert the string to a float, then fix it to two decimals (but the toFixed returns a string), and finally parse it again.

Answer 3

You can store your price as a string

You can use Number(string)

for your calculations.

example

Number("34.50") == 34.5

also

Number("35.65") == 35.65

If you're comfortable with the Number function , you can go with it.

Answer 4

I have tried this for my case and it'll work fine.

var multiplied_value = parseFloat(given_quantity*given_price).toFixed(3);

Sample output:

9.007

Answer 5

You can use .toFixed() to for float value 2 digits

Exampale

let newValue = parseFloat(9.990000).toFixed(2)

//output
9.99

Answer 6

@sd 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.

Answer 7

Solution for FormArray controllers 

Initialize FormArray form Builder

  formInitilize() {
    this.Form = this._formBuilder.group({
      formArray: this._formBuilder.array([this.createForm()])
    });
  }

Create Form

  createForm() {
    return (this.Form = this._formBuilder.group({
      convertodecimal: ['']
    }));
  }

Set Form Values into Form Controller

  setFormvalues() {
    this.Form.setControl('formArray', this._formBuilder.array([]));
    const control = <FormArray>this.resourceBalanceForm.controls['formArray'];
    this.ListArrayValues.forEach((x) => {
      control.push(this.buildForm(x));
    });
  }

  private buildForm(x): FormGroup {
    const bindvalues= this._formBuilder.group({
      convertodecimal: x.ArrayCollection1? parseFloat(x.ArrayCollection1[0].name).toFixed(2) : '' // Option for array collection
// convertodecimal: x.number.toFixed(2)    --- option for two decimal value 
    });

    return bindvalues;
  }

Answer 8

The solution that work for me is the following

parseFloat(value)

Answer 9

ceil from lodash is probably the best

_.ceil("315.9250488",2) 
_.ceil(315.9250488,2) 
_.ceil(undefined,2)
_.ceil(null,2)
_.ceil("",2)

will work also with a number and it's safe

Answer 10

If your objective is to parse, and your input might be a literal, then you'd expect a float and toFixed won't provide that, so here are two simple functions to provide this:

function parseFloat2Decimals(value) {
    return parseFloat(parseFloat(value).toFixed(2));
}

function parseFloat2Decimals(value,decimalPlaces) {
    return parseFloat(parseFloat(value).toFixed(decimalPlaces));
}

Answer 11

For what its worth: A decimal number, is a decimal number, you either round it to some other value or not. Internally, it will approximate a decimal fraction according to the rule of floating point arthmetic and handling. It stays a decimal number (floating point, in JS a double) internally, no matter how you many digits you want to display it with.

To present it for display, you can choose the precision of the display to whatever you want by string conversion. Presentation is a display issue, not a storage thing.

Answer 12

Please use below function if you don't want to round off.

function ConvertToDecimal(num) {
    num = num.toString(); //If it's not already a String
    num = num.slice(0, (num.indexOf(".")) + 3); //With 3 exposing the hundredths place
   alert('M : ' +  Number(num)); //If you need it back as a Number    
}

Answer 13

When you use toFixed, it always returns the value as a string. This sometimes complicates the code. To avoid that, you can make an alternative method for Number.

Number.prototype.round = function(p) {
  p = p || 10;
  return parseFloat( this.toFixed(p) );
};

and use:

var n = 22 / 7; // 3.142857142857143
n.round(3); // 3.143

or simply:

(22/7).round(3); // 3.143

Answer 14

To return a number, add another layer of parentheses. Keeps it clean.

var twoPlacedFloat = parseFloat((10.02745).toFixed(2));

Answer 15

Try this (see comments in code):

function fixInteger(el) {
    // this is element's value selector, you should use your own
    value = $(el).val();
    if (value == '') {
        value = 0;
    }
    newValue = parseInt(value);
    // if new value is Nan (when input is a string with no integers in it)
    if (isNaN(newValue)) {
        value = 0;
        newValue = parseInt(value);
    }
    // apply new value to element
    $(el).val(newValue);
}

function fixPrice(el) {
    // this is element's value selector, you should use your own
    value = $(el).val();
    if (value == '') {
        value = 0;
    }
    newValue = parseFloat(value.replace(',', '.')).toFixed(2);
    // if new value is Nan (when input is a string with no integers in it)
    if (isNaN(newValue)) {
        value = 0;
        newValue = parseFloat(value).toFixed(2);
    }
    // apply new value to element
    $(el).val(newValue);
}

Answer 16

You can use toFixed() to do that

var twoPlacedFloat = parseFloat(yourString).toFixed(2)

Answer 17

I've got other solution.

You can use round() to do that instead toFixed()

var twoPlacedFloat = parseFloat(yourString).round(2)