分享5个javascript的数字格式化函数

Javascript没有任何内建的格式化函数，这里我们通过Google收集了5个javascript的数字格式化函数，希望对于大家的web开发能够带来方便。

十进制四舍五入

这两段代码帮助你做到四舍五入，对于你显示价格或者订单比较有用：

代码1：

01	function CurrencyFormatted(amount) {

02	var i = parseFloat(amount);

03	if(isNaN(i)) { i = 0.00; }

04	var minus = '';

05	if(i < 0) { minus = '-'; }

06	i = Math.abs(i);

07	i = parseInt((i + .005) * 100);

08	i = i / 100;

09	s = new String(i);

10	if(s.indexOf('.') < 0) { s += '.00'; }

11	if(s.indexOf('.') == (s.length - 2)) { s += '0'; }

12	s = minus + s;

13

return s;

14

}

15

16

/**

17	*   Usage:  CurrencyFormatted(12345.678);

18	*   result: 12345.68

19

**/

代码2：

01	function format_number(pnumber,decimals){

02	if (isNaN(pnumber)) { return 0};

03	if (pnumber=='') { return 0};

04

05	var snum = new String(pnumber);

06	var sec = snum.split('.');

07	var whole = parseFloat(sec[0]);

08	var result = '';

09

10	if(sec.length > 1){

11	var dec = new String(sec[1]);

12	dec = String(parseFloat(sec[1])/Math.pow(10,(dec.length - decimals)));

13	dec = String(whole + Math.round(parseFloat(dec))/Math.pow(10,decimals));

14	var dot = dec.indexOf('.');

15	if(dot == -1){

16	dec += '.';

17	dot = dec.indexOf('.');

18

}

19	while(dec.length <= dot + decimals) { dec += '0'; }

20	result = dec;

21

} else{

22

var dot;

23	var dec = new String(whole);

24	dec += '.';

25	dot = dec.indexOf('.');

26	while(dec.length <= dot + decimals) { dec += '0'; }

27	result = dec;

28

}

29	return result;

30

}

31

32

/**

33	*   Usage:  format_number(12345.678, 2);

34	*   result: 12345.68

35

**/

添加逗号

这俩段代码帮助你添加逗号到每三位数字中，这让大的数字比较容易查看。

01	function CommaFormatted(amount) {

02	var delimiter = ","; // replace comma if desired

03	amount = new String(amount);

04	var a = amount.split('.',2)

05	var d = a[1];

06	var i = parseInt(a[0]);

07	if(isNaN(i)) { return ''; }

08	var minus = '';

09	if(i < 0) { minus = '-'; }

10	i = Math.abs(i);

11	var n = new String(i);

12	var a = [];

13	while(n.length > 3)

14

{

15	var nn = n.substr(n.length-3);

16	a.unshift(nn);

17	n = n.substr(0,n.length-3);

18

}

19	if(n.length > 0) { a.unshift(n); }

20	n = a.join(delimiter);

21	if(d.length < 1) { amount = n; }

22	else { amount = n + '.' + d; }

23	amount = minus + amount;

24	return amount;

25

}

26

27

/**

28	*   Usage:  CommaFormatted(12345678);

29	*   result: 12,345,678

30

**/

代码2：

01	function addCommas(nStr) {

02	nStr += '';

03	var x = nStr.split('.');

04	var x1 = x[0];

05	var x2 = x.length >; 1 ? '.' + x[1] : '';

06	var rgx = /(d+)(d{3})/;

07

08	while (rgx.test(x1)) {

09	x1 = x1.replace(rgx, '$1' + ',' + '$2');

10

}

11

12	return x1 + x2;

13

}

14

15

/**

16	*   Usage:  addCommas(12345678);

17	*   result: 12,345,678

18

**/

数字格式化，来自PHP

这段javascript代码功能设计来自PHP的nubmer_format功能。能够四舍五入并且加入逗号分隔。而且可以自定义10进制分隔。

01	function number_format (number, decimals, dec_point, thousands_sep) {

02

03	number = (number + '').replace(/[^0-9+-Ee.]/g, '');

04	var n = !isFinite(+number) ? 0 : +number,

05	prec = !isFinite(+decimals) ? 0 : Math.abs(decimals),

06	sep = (typeof thousands_sep === 'undefined') ? ',' : thousands_sep,

07	dec = (typeof dec_point === 'undefined') ? '.' : dec_point,

08

s = '',

09	toFixedFix = function (n, prec) {

10	var k = Math.pow(10, prec);

11	return '' + Math.round(n * k) / k;

12

};

13	// Fix for IE parseFloat(0.55).toFixed(0) = 0;

14	s = (prec ? toFixedFix(n, prec) : '' + Math.round(n)).split('.');

15	if (s[0].length > 3) {

16	s[0] = s[0].replace(/B(?=(?:d{3})+(?!d))/g, sep);

17

}

18	if ((s[1] || '').length < prec) {

19	s[1] = s[1] || '';

20	s[1] += new Array(prec - s[1].length + 1).join('0');

21

}

22	return s.join(dec);

23

}

24

25

/**

26	*   Usage:  number_format(123456.789, 2, '.', ',');

27	*   result: 123,456.79

28

**/

添加一个英文的排序后缀

01	Number.prototype.toOrdinal = function() {

02	var n = this % 100;

03	var suffix = ['th', 'st', 'nd', 'rd', 'th'];

04	var ord = n < 21 ? (n < 4 ? suffix[n] : suffix[0]) : (n % 10 > 4 ? suffix[0] : suffix[n % 10]);

05	return this + ord;

06

}

07

08

/*

09	*   Usage:

10	*   var myNumOld = 23

11	*   var myNumNew = myNumOld.toOrdinal()

12	*   Result: 23rd

13

*/

除去非数字的字符

01	function stripNonNumeric( str )

02

{

03	str += '';

04	var rgx = /^d|.|-$/;

05	var out = '';

06	for( var i = 0; i < str.length; i++ )

07

{

08	if( rgx.test( str.charAt(i) ) ){

09	if( !( ( str.charAt(i) == '.' && out.indexOf( '.' ) != -1 ) ||

10	( str.charAt(i) == '-' && out.length != 0 ) ) ){

11	out += str.charAt(i);

12

}

13

}

14

}

15	return out;

16

}

17

18

/*

19	*   Usage: stripNonNumeric('123et45dhs6.789');

20	*   Result: 123456.789

21

*/

原文来自：分享5个javascript的数字格式化函数