Date对象的扩展

getDaysInMonth：获取某月有多少天

Date.getDaysInMonth = function (year, month) { var days = 0; switch (month) { case 1: case 3: case 5: case 7: case 8: case 10: case 12: days = 31 break; case 4: case 6: case 9: case 11: days = 30; break; case 2: if (year % 400 == 0 || (year % 4 == 0 && year % 100 != 0)) days = 29; else days = 28; break; } return days; } if (typeof Date.prototype.format == 'undefined') { Date.prototype.format = function (mask) { var d = this; var zeroize = function (value, length) { if (!length) length = 2; value = String(value); for (var i = 0, zeros = ''; i < (length - value.length); i++) { zeros += '0'; } return zeros + value; }; return mask.replace(/"[^"]*"|'[^']*'|\b(?:d{1,4}|m{1,4}|yy(?:yy)?|([hHMstT])\1?|[lLZ])\b/g, function ($0) { switch ($0) { case 'd': return d.getDate(); case 'dd': return zeroize(d.getDate()); case 'ddd': return ['Sun', 'Mon', 'Tue', 'Wed', 'Thr', 'Fri', 'Sat'][d.getDay()]; case 'dddd': return ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'][d.getDay()]; case 'M': return d.getMonth() + 1; case 'MM': return zeroize(d.getMonth() + 1); case 'MMM': return ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'][d.getMonth()]; case 'MMMM': return ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'][d.getMonth()]; case 'yy': return String(d.getFullYear()).substr(2); case 'yyyy': return d.getFullYear(); case 'h': return d.getHours() % 12 || 12; case 'hh': return zeroize(d.getHours() % 12 || 12); case 'H': return d.getHours(); case 'HH': return zeroize(d.getHours()); case 'm': return d.getMinutes(); case 'mm': return zeroize(d.getMinutes()); case 's': return d.getSeconds(); case 'ss': return zeroize(d.getSeconds()); case 'l': return zeroize(d.getMilliseconds(), 3); case 'L': var m = d.getMilliseconds(); if (m > 99) m = Math.round(m / 10); return zeroize(m); case 'tt': return d.getHours() < 12 ? 'am' : 'pm'; case 'TT': return d.getHours() < 12 ? 'AM' : 'PM'; case 'Z': return d.toUTCString().match(/[A-Z]+$/); // Return quoted strings with the surrounding quotes removed default: return $0.substr(1, $0.length - 2); } }); }; } 

使用原生js实现复制对象及扩展

jQuery的extend()方法能很方便的实现扩展对象方法，这里要实现的是：使用原生js实现复制对象，扩展对象，类似jQuery中的extend()方法

var obj1 = { name : 'trigkit4', age : 22 }; var obj2 = { name : 'frank', age : 21, speak : function(){ alert("hi, I'm + name "); } }; var obj3 ={ age : 20 }; function cloneObj(oldObj) { //复制对象方法 if (typeof(oldObj) != 'object') return oldObj; if (oldObj == null) return oldObj; var newObj = Object(); for (var i in oldObj) newObj[i] = cloneObj(oldObj[i]); return newObj; } function extendObj() { //扩展对象 var args = arguments;//将传递过来的参数数组赋值给args变量 if (args.length < 2) return; var temp = cloneObj(args[0]); //调用复制对象方法 for (var n = 1; n < args.length; n++) { for (var i in args[n]) { temp[i] = args[n][i]; } } return temp; } var obj =extendObj(obj1,obj2,obj3); console.log(obj);//{ name: 'frank', age: 20, speak: [Function] } console.log(obj1);//{ name: 'trigkit4', age: 22 } console.log(obj2);//{ name: 'frank', age: 21, speak: [Function] } console.log(obj3);//{ age: 20 } 

es5-safe 模块

es5-safe 模块里，仅扩展了可以较好实现的可以安全使用的部分方法，包括：