// 和PHP一样的时间戳格式化函数 // @param  {string} format    格式 // @param  {int}    timestamp 要格式化的时间 默认为当前时间 // @return {string}           格式化的时间字符串 function date ( format, timestamp ) {     var a, jsdate=((timestamp) ? new Date(timestamp*1000) : new Date());     var pad = function(n, c){         if( (n = n + "").length < c ) {             return new Array(++c - n.length).join("0") + n;         } else {             return n;         }     };     var txt_weekdays = ["Sunday","Monday","Tuesday","Wednesday", "Thursday","Friday","Saturday"];             var txt_ordin = {1:"st",2:"nd",3:"rd",21:"st",22:"nd",23:"rd",31:"st"};     var txt_months = ["", "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"];     var f = {         // Day             d: function(){                 return pad(f.j(), 2);             },             D: function(){                 t = f.l(); return t.substr(0,3);             },             j: function(){                 return jsdate.getDate();             },             l: function(){                 return txt_weekdays[f.w()];             },             N: function(){                 return f.w() + 1;             },             S: function(){                 return txt_ordin[f.j()] ? txt_ordin[f.j()] : 'th';             },             w: function(){                 return jsdate.getDay();             },             z: function(){                 return (jsdate - new Date(jsdate.getFullYear() + "/1/1")) / 864e5 >> 0;             },         // Week             W: function(){                 var a = f.z(), b = 364 + f.L() - a;                 var nd2, nd = (new Date(jsdate.getFullYear() + "/1/1").getDay() || 7) - 1;                 if(b <= 2 && ((jsdate.getDay() || 7) - 1) <= 2 - b){                     return 1;                 } else{                     if(a <= 2 && nd >= 4 && a >= (6 - nd)){                         nd2 = new Date(jsdate.getFullYear() - 1 + "/12/31");                         return date("W", Math.round(nd2.getTime()/1000));                     } else{                         return (1 + (nd <= 3 ? ((a + nd) / 7) : (a - (7 - nd)) / 7) >> 0);                     }                 }             },         // Month             F: function(){                 return txt_months[f.n()];             },             m: function(){                 return pad(f.n(), 2);             },             M: function(){                 t = f.F(); return t.substr(0,3);             },             n: function(){                 return jsdate.getMonth() + 1;             },             t: function(){                 var n;                 if( (n = jsdate.getMonth() + 1) == 2 ){                     return 28 + f.L();                 } else{                     if( n & 1 && n < 8 || !(n & 1) && n > 7 ){                         return 31;                     } else{                         return 30;                     }                 }             },         // Year             L: function(){                 var y = f.Y();                 return (!(y & 3) && (y % 1e2 || !(y % 4e2))) ? 1 : 0;             },             //o not supported yet             Y: function(){                 return jsdate.getFullYear();             },             y: function(){                 return (jsdate.getFullYear() + "").slice(2);             },         // Time             a: function(){                 return jsdate.getHours() > 11 ? "pm" : "am";             },             A: function(){                 return f.a().toUpperCase();             },             B: function(){                 // peter paul koch:                 var off = (jsdate.getTimezoneOffset() + 60)*60;                 var theSeconds = (jsdate.getHours() * 3600) +                                  (jsdate.getMinutes() * 60) +                                   jsdate.getSeconds() + off;                 var beat = Math.floor(theSeconds/86.4);                 if (beat > 1000) beat -= 1000;                 if (beat < 0) beat += 1000;                 if ((String(beat)).length == 1) beat = "00"+beat;                 if ((String(beat)).length == 2) beat = "0"+beat;                 return beat;             },             g: function(){                 return jsdate.getHours() % 12 || 12;             },             G: function(){                 return jsdate.getHours();             },             h: function(){                 return pad(f.g(), 2);             },             H: function(){                 return pad(jsdate.getHours(), 2);             },             i: function(){                 return pad(jsdate.getMinutes(), 2);             },             s: function(){                 return pad(jsdate.getSeconds(), 2);             },             //u not supported yet         // Timezone             //e not supported yet             //I not supported yet             O: function(){                var t = pad(Math.abs(jsdate.getTimezoneOffset()/60*100), 4);                if (jsdate.getTimezoneOffset() > 0) t = "-" + t; else t = "+" + t;                return t;             },             P: function(){                 var O = f.O();                 return (O.substr(0, 3) + ":" + O.substr(3, 2));             },             //T not supported yet             //Z not supported yet         // Full Date/Time             c: function(){                 return f.Y() + "-" + f.m() + "-" + f.d() + "T" + f.h() + ":" + f.i() + ":" + f.s() + f.P();             },             //r not supported yet             U: function(){                 return Math.round(jsdate.getTime()/1000);             }     };     return format.replace(/[\\]?([a-zA-Z])/g, function(t, s){         if( t!=s ){             // escaped             ret = s;         } else if( f[s] ){             // a date function exists             ret = f[s]();         } else{             // nothing special             ret = s;         }         return ret;     }); }