日期:2014-05-16 浏览次数:20431 次
javascript:void(alert("1:2:3".split(/(:)/)));
/* Cross-Browser Split 1.0.1 (c) Steven Levithan <stevenlevithan.com>; MIT License An ECMA-compliant, uniform cross-browser split method */ var cbSplit; // avoid running twice, which would break `cbSplit._nativeSplit`'s reference to the native `split` if (!cbSplit) { cbSplit = function (str, separator, limit) { // if `separator` is not a regex, use the native `split` if (Object.prototype.toString.call(separator) !== "[object RegExp]") { return cbSplit._nativeSplit.call(str, separator, limit); } var output = [], lastLastIndex = 0, flags = (separator.ignoreCase ? "i" : "") + (separator.multiline ? "m" : "") + (separator.sticky ? "y" : ""), separator = RegExp(separator.source, flags + "g"), // make `global` and avoid `lastIndex` issues by working with a copy separator2, match, lastIndex, lastLength; str = str + ""; // type conversion if (!cbSplit._compliantExecNpcg) { separator2 = RegExp("^" + separator.source + "$(?!\\s)", flags); // doesn't need /g or /y, but they don't hurt } /* behavior for `limit`: if it's... - `undefined`: no limit. - `NaN` or zero: return an empty array. - a positive number: use `Math.floor(limit)`. - a negative number: no limit. - other: type-convert, then use the above rules. */ if (limit === undefined || +limit < 0) { limit = Infinity; } else { limit = Math.floor(+limit); if (!limit) { return []; } } while (match = separator.exec(str)) { lastIndex = match.index + match[0].length; // `separator.lastIndex` is not reliable cross-browser if (lastIndex > lastLastIndex) { output.push(str.slice(lastLastIndex, match.index)); // fix browsers whose `exec` methods don't consistently return `undefined` for nonparticipating capturing groups if (!cbSplit._compliantExecNpcg && match.length > 1) { match[0].replace(separator2, function () { for (var i = 1; i < arguments.length - 2; i++) { if (arguments[i] === undefined) { match[i] = undefined; } } }); } if (match.length > 1 && match.index < str.length) { Array.prototype.push.apply(output, match.slice(1)); } lastLength = match[0].length; lastLastIndex = lastIndex; if (output.length >= limit) { break; } } if (separator.lastIndex === match.index) { separator.lastIndex++; // avoid an infinite loop } } if (lastLastIndex === str.length) { if (lastLength || !separator.test("")) { output.push(""); } } else { output.push(str.slice(lastLastIndex)); } return output.length > limit ? output.slice(0, limit) : output; }; cbSplit._compliantExecNpcg = /()??/.exec("")[1] === undefined; // NPCG: nonparticipating capturing group cbSplit._nativeSplit = String.prototype.split; } // end `if (!cbSplit)` // for convenience... String.prototype.split = function (separator, limit) { return cbSplit(this, separator, limit); };