兼容低版本IE的JScript5.5实现

< 0 || n > 20) { @if (@_jscript_version < 5) return null; @else var e = new Error(-2146823262, "The number of fractional digits is out of range"); e.name = "RangeError"; e.message = e.description; throw(e); @end } } var s, d, e, len; s = this.toString().split("e"); d = parseFloat(s[0]); e = 0; if (typeof(s[1]) != "undefined") { e = parseInt(s[1]); } s = d.toString().split("."); if (typeof(s[1]) != "undefined") { e = e - s[1].length; d = s[0] + s[1]; d = d.replace(/^0+/g, ""); if (d == "") d = "0"; } s = d.toString(); len = s.length - 1; e += len; if (len < n) { s += repeat("0", n - len); } else if (len > n) { s = Math.round(parseFloat("." + s) * Math.pow(10, n + 1)).toString(); if ((s.length - 1) > n) { e += 1; s = Math.round(parseFloat("." + s) * Math.pow(10, n + 1)).toString(); } } if (e >= 0) { e = "+" + e; } if (n == 0) { return s + "e" + e; } else { return s.substr(0, 1) + "." + s.substr(1) + "e" + e; } } Number.prototype.toFixed = function (n) { function repeat(s, n) { var out = ""; for (var i = 0; i < n; i++) { out += s; } return out; } if (!n) { n = 0; } else { n = parseInt(n); if (n < 0 || n > 20) { @if (@_jscript_version < 5) return null; @else var e = new Error(-2146823262, "The number of fractional digits is out of range"); e.name = "RangeError"; e.message = e.description; throw(e); @end } } var s, d, e, len; s = this.toString().split("e"); d = parseFloat(s[0]); e = 0; if (typeof(s[1]) != "undefined") { e = parseInt(s[1]); } s = d.toString().split("."); if (typeof(s[1]) != "undefined") { e = e - s[1].length; d = s[0] + s[1]; d = d.replace(/^0+/g, ""); if (d == "") d = "0"; } s = d.toString(); len = s.length - 1; if (e >= 0) { s += repeat("0", e); if (n > 0) { s += "." + repeat("0", n); } } else if (-e <= n) { s = repeat("0", 1 - e - s.length) + s; s = s.substr(0, s.length + e) + "." + s.substr(s.length + e) + repeat("0", n + e); } else { s = repeat("0", 1 - e - s.length) + s; d = parseFloat(s.substr(0, s.length + e) + "." + s.substr(s.length + e)); s = Math.round(d * Math.pow(10, n)).toString(); if (n > 0) { s = repeat("0", n - s.length + 1) + s; s = s.substr(0, s.length - n) + "." + s.substr(s.length - n); } } return s; } Number.prototype.toPrecision = function (n) { function repeat(s, n) { var out = ""; for (var i = 0; i