Format numbers in JavaScript similar to C#

Question

Is there a simple way to format numbers in JavaScript, similar to the formatting methods available in C# (or VB.NET) via ToString(\"format_provider\") or

Answer 1

For example:

var flt = '5.99';
var nt = '6';

var rflt = parseFloat(flt);
var rnt = parseInt(nt);

Answer 2

To further jfriend00's answer (I dont't have enough points to comment) I have extended his/her answer to the following:

function log(args) {
    var str = "";
    for (var i = 0; i < arguments.length; i++) {
        if (typeof arguments[i] === "object") {
            str += JSON.stringify(arguments[i]);
        } else {
            str += arguments[i];
        }
    }
    var div = document.createElement("div");
    div.innerHTML = str;
    document.body.appendChild(div);
}

Number.prototype.addCommas = function (str) {
    if (str === undefined) {
    	str = this;
    }
    
    var parts = (str + "").split("."),
        main = parts[0],
        len = main.length,
        output = "",
        first = main.charAt(0),
        i;
    
    if (first === '-') {
        main = main.slice(1);
        len = main.length;    
    } else {
    	  first = "";
    }
    i = len - 1;
    while(i >= 0) {
        output = main.charAt(i) + output;
        if ((len - i) % 3 === 0 && i > 0) {
            output = "," + output;
        }
        --i;
    }
    // put sign back
    output = first + output;
    // put decimal part back
    if (parts.length > 1) {
        output += "." + parts[1];
    }
    return output;
}

var testCases = [
    1, 12, 123, -1234, 12345, 123456, -1234567, 12345678, 123456789,
    -1.1, 12.1, 123.1, 1234.1, -12345.1, -123456.1, -1234567.1, 12345678.1, 123456789.1
];
 
for (var i = 0; i < testCases.length; i++) {
	log(testCases[i].addCommas());
}
 
/*for (var i = 0; i < testCases.length; i++) {
    log(Number.addCommas(testCases[i]));
}*/

Answer 3

Using JQuery.

$(document).ready(function()
 {
    //Only number and one dot
    function onlyDecimal(element, decimals)
    {
        $(element).keypress(function(event)
        {
            num = $(this).val() ;
            num = isNaN(num) || num === '' || num === null ? 0.00 : num ;
            if ((event.which != 46 || $(this).val().indexOf('.') != -1) && (event.which < 48 || event.which > 57))
            {
                event.preventDefault();

            }
            if($(this).val() == parseFloat(num).toFixed(decimals))
            {
                event.preventDefault();
            }
        });
    }

     onlyDecimal("#TextBox1", 3) ;



});

Answer 4

May I suggest numbro for locale based formatting and number-format.js for the general case. A combination of the two depending on use-case may help.

Answer 5

I made a simple function, maybe someone can use it

function secsToTime(secs){
  function format(number){
    if(number===0){
      return '00';
    }else {
      if (number < 10) {
          return '0' + number
      } else{
          return ''+number;
      }
    }
  }

  var minutes = Math.floor(secs/60)%60;
  var hours = Math.floor(secs/(60*60))%24;
  var days = Math.floor(secs/(60*60*24));
  var seconds = Math.floor(secs)%60;

  return (days>0? days+"d " : "")+format(hours)+':'+format(minutes)+':'+format(seconds);
}

this can generate the followings outputs:

• 5d 02:53:39
• 4d 22:15:16
• 03:01:05
• 00:00:00

Answer 6

To get a decimal with 2 numbers after the comma, you could just use:

function nformat(a) {
   var b = parseInt(parseFloat(a)*100)/100;
   return b.toFixed(2);
}