Javascript之Number_format

 

// Formats a number with grouped thousands  
// *     example 1: number_format(1234.56);
// *     returns 1: '1,235'
// *     example 2: number_format(1234.56, 2, ',', ' ');
// *     returns 2: '1 234,56'
// *     example 3: number_format(1234.5678, 2, '.', '');
// *     returns 3: '1234.57'
// *     example 4: number_format(67, 2, ',', '.');    
// *     returns 4: '67,00'
// *     example 5: number_format(1000);
// *     returns 5: '1,000'
// *     example 6: number_format(67.311, 2);
// *     returns 6: '67.31'
// *     example 7: number_format(1000.55, 1);
// *     returns 7: '1,000.6'
// *     example 8: number_format(67000, 5, ',', '.');
// *     returns 8: '67.000,00000'
// *     example 9: number_format(0.9, 0);    
// *     returns 9: '1'
// *     example 10: number_format('1.20', 2);
// *     returns 10: '1.20'
// *     example 11: number_format('1.20', 4);
// *     returns 11: '1.2000'    
// *     example 12: number_format('1.2000', 3);
// *     returns 12: '1.200'
/**
 * number_format
 *
 * @param int or float number
 * @param int          decimals
 * @param string       dec_point
 * @param string       thousands_sep
 * @return string
 */
function number_format(number, decimals, dec_point, thousands_sep) {
    var n = !isFinite(+number) ? 0 : +number,
        prec = !isFinite(+decimals) ? 0 : Math.abs(decimals),
        sep = (typeof thousands_sep === 'undefined') ? ',' : thousands_sep,
        dec = (typeof dec_point === 'undefined') ? '.' : dec_point,
        s = '',
        toFixedFix = function (n, prec) {
            var k = Math.pow(10, prec);
            return '' + Math.round(n * k) / k;        };
    // Fix for IE parseFloat(0.55).toFixed(0) = 0;
    s = (prec ? toFixedFix(n, prec) : '' + Math.round(n)).split('.');
    if (s[0].length > 3) {
        s[0] = s[0].replace(//B(?=(?:/d{3})+(?!/d))/g, sep);    }
    if ((s[1] || '').length < prec) {
        s[1] = s[1] || '';
        s[1] += new Array(prec - s[1].length + 1).join('0');
    }    return s.join(dec);
}