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Javascript number formatter (Java DecimalFormat Implemented in Javascript)
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/** | |
* @class DecimalFormat | |
* @constructor | |
* @param {String} formatStr | |
* @author Oskan Savli | |
*/ | |
function DecimalFormat(formatStr) | |
{ | |
/** | |
* @fieldOf DecimalFormat | |
* @type String | |
*/ | |
this.prefix = ''; | |
/** | |
* @fieldOf DecimalFormat | |
* @type String | |
*/ | |
this.suffix = ''; | |
/** | |
* @description Grouping size | |
* @fieldOf DecimalFormat | |
* @type String | |
*/ | |
this.comma = 0; | |
/** | |
* @description Minimum integer digits to be displayed | |
* @fieldOf DecimalFormat | |
* @type Number | |
*/ | |
this.minInt = 1; | |
/** | |
* @description Minimum fractional digits to be displayed | |
* @fieldOf DecimalFormat | |
* @type String | |
*/ | |
this.minFrac = 0; | |
/** | |
* @description Maximum fractional digits to be displayed | |
* @fieldOf DecimalFormat | |
* @type String | |
*/ | |
this.maxFrac = 0; | |
// get prefix | |
for (var i=0; i<formatStr.length; i++) { | |
if (formatStr.charAt(i) == '#' || formatStr.charAt(i) == '0') { | |
this.prefix = formatStr.substring(0,i); | |
formatStr = formatStr.substring(i); | |
break; | |
} | |
} | |
// get suffix | |
this.suffix = formatStr.replace(/[#]|[0]|[,]|[.]/g , ''); | |
// get number as string | |
var numberStr = formatStr.replace(/[^0#,.]/g , ''); | |
var intStr = ''; | |
var fracStr = ''; | |
var point = numberStr.indexOf('.'); | |
if (point != -1) { | |
intStr = numberStr.substring(0,point); | |
fracStr = numberStr.substring(point+1); | |
} | |
else { | |
intStr = numberStr; | |
} | |
var commaPos = intStr.lastIndexOf(','); | |
if (commaPos != -1) { | |
this.comma = intStr.length - 1 - commaPos; | |
} | |
intStr = intStr.replace(/[,]/g , ''); // remove commas | |
fracStr = fracStr.replace(/[,]|[.]+/g , ''); | |
this.maxFrac = fracStr.length; | |
var tmp = intStr.replace(/[^0]/g , ''); // remove all except zero | |
if (tmp.length > this.minInt) | |
this.minInt = tmp.length; | |
tmp = fracStr.replace(/[^0]/g , ''); | |
this.minFrac = tmp.length; | |
} | |
/** | |
* @description Formats given value | |
* @methodOf DecimalFormat | |
* @param {String} numberStr | |
* @return {String} Formatted number | |
* @author Oskan Savli | |
*/ | |
DecimalFormat.prototype.format = function(numStr) { // 1223.06 --> $1,223.06 | |
// remove prefix, suffix and commas | |
var numberStr = this.formatBack(numStr).toLowerCase(); | |
// do not format if not a number | |
if (isNaN(numberStr) || numberStr.length == 0) | |
return numStr; | |
//scientific numbers | |
if (i = numberStr.indexOf("e") != -1) { | |
var n = Number(numberStr); | |
if (n=="Infinity" || n=="-Infinity") return numberStr; | |
numberStr = n+""; | |
if(numberStr.indexOf('e') != -1) return numberStr; | |
} | |
var negative = false; | |
// remove sign | |
if (numberStr.charAt(0) == '-') { | |
negative = true; | |
numberStr = numberStr.substring(1); | |
} | |
else if (numberStr.charAt(0) == '+') { | |
numberStr = numberStr.substring(1); | |
} | |
var point = numberStr.indexOf('.'); // position of point character | |
var intStr = ''; | |
var fracStr = ''; | |
if (point != -1) { | |
intStr = numberStr.substring(0,point); | |
fracStr = numberStr.substring(point+1); | |
} | |
else { | |
intStr = numberStr; | |
} | |
fracStr = fracStr.replace(/[.]/ , ''); // remove other point characters | |
var isPercentage = this.suffix && this.suffix.charAt(0) === '%'; | |
// if percentage, number will be multiplied by 100. | |
var minInt = this.minInt, minFrac = this.minFrac, maxFrac = this.maxFrac; | |
if (isPercentage) { | |
minInt -= 2; | |
minFrac += 2; | |
maxFrac += 2; | |
} | |
if (fracStr.length > maxFrac) { // round | |
//case 6143 | |
var num = new Number('0.' + fracStr); | |
num = (maxFrac == 0)? Math.round(num) : num.toFixed(maxFrac); | |
// toFixed method has bugs on IE (0.7 --> 0) | |
fracStr = num.toString(10).substr(2); | |
var c = (num>=1)? 1:0; //carry | |
var x, i=intStr.length-1; | |
while (c) { //increment intStr | |
if (i==-1) { | |
intStr = '1'+intStr; | |
break; | |
} | |
else { | |
x = intStr.charAt(i); | |
if (x==9) {x='0'; c=1;} | |
else {x = (++x)+''; c=0;} | |
intStr = intStr.substring(0,i) + x + intStr.substring(i+1,intStr.length); | |
i--; | |
} | |
} | |
} | |
for (var i=fracStr.length; i<minFrac; i++) { // if minFrac=4 then 1.12 --> 1.1200 | |
fracStr = fracStr + '0'; | |
} | |
while (fracStr.length > minFrac && fracStr.charAt(fracStr.length-1) == '0') { // if minInt=4 then 00034 --> 0034) | |
fracStr = fracStr.substring(0,fracStr.length-1); | |
} | |
for (var i=intStr.length; i<minInt; i++) { // if minInt=4 then 034 --> 0034 | |
intStr = '0' + intStr; | |
} | |
while (intStr.length > minInt && intStr.charAt(0) == '0') { // if minInt=4 then 00034 --> 0034) | |
intStr = intStr.substring(1); | |
} | |
if (isPercentage) { // multiply by 100 | |
intStr += fracStr.substring(0,2); | |
fracStr = fracStr.substring(2); | |
} | |
var j = 0; | |
for(var i=intStr.length; i>0; i--) { // add commas | |
if (j != 0 && j%this.comma == 0) { | |
intStr = intStr.substring(0,i) + ',' + intStr.substring(i); | |
j = 0; | |
} | |
j++; | |
} | |
var formattedValue; | |
if (fracStr.length > 0) | |
formattedValue = this.prefix + intStr + '.' + fracStr + this.suffix; | |
else | |
formattedValue = this.prefix + intStr + this.suffix; | |
if (negative) { | |
formattedValue = '-' + formattedValue; | |
} | |
return formattedValue; | |
} | |
/** | |
* @description Converts formatted value back to non-formatted value | |
* @methodOf DecimalFormat | |
* @param {String} fNumberStr Formatted number | |
* @return {String} Original number | |
* @author Oskan Savli | |
*/ | |
DecimalFormat.prototype.formatBack = function(fNumStr) { // $1,223.06 --> 1223.06 | |
fNumStr += ''; //ensure it is string | |
if (!fNumStr) return ''; //do not return undefined or null | |
if (!isNaN(fNumStr)) return this.getNumericString(fNumStr); | |
var fNumberStr = fNumStr; | |
var negative = false; | |
if (fNumStr.charAt(0) == '-') { | |
fNumberStr = fNumberStr.substr(1); | |
negative = true; | |
} | |
var pIndex = fNumberStr.indexOf(this.prefix); | |
var sIndex = (this.suffix == '')? fNumberStr.length : fNumberStr.indexOf(this.suffix, this.prefix.length+1); | |
if (pIndex == 0 && sIndex > 0) { | |
// remove suffix | |
fNumberStr = fNumberStr.substr(0,sIndex); | |
// remove prefix | |
fNumberStr = fNumberStr.substr(this.prefix.length); | |
// remove commas | |
fNumberStr = fNumberStr.replace(/,/g , ''); | |
if (negative) | |
fNumberStr = '-' + fNumberStr; | |
if (!isNaN(fNumberStr)) | |
return this.getNumericString(fNumberStr); | |
} | |
return fNumStr; | |
} | |
/** | |
* @description We shouldn't return strings like 1.000 in formatBack method. | |
* However, using only Number(str) is not enough, because it omits . in big numbers | |
* like 23423423423342234.34 => 23423423423342236 . There's a conflict in cases | |
* 6143 and 6541. | |
* @methodOf DecimalFormat | |
* @param {String} str Numberic string | |
* @return {String} Corrected numeric string | |
* @author Serdar Bicer | |
*/ | |
DecimalFormat.prototype.getNumericString = function(str){ | |
//first convert to number | |
var num = new Number(str); | |
//check if there is a missing dot | |
var numStr = num + ''; | |
if (str.indexOf('.')>-1 && numStr.indexOf('.')<0){ | |
//check if original string has all zeros after dot or not | |
for (var i=str.indexOf('.')+1;i<str.length;i++){ | |
//if not, this means we lost precision | |
if (str.charAt(i) !== '0') return str; | |
} | |
return numStr; | |
} | |
return str; | |
} |
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