JS date函数封装

/**

• 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(timestamp1000) : 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(){return f.l().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(){return f.F().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 = fs;
  } else{
  // nothing special
  ret = s;
  }
  return ret;
  });
  }

var ms = date(‘Y-m-d’,‘1350052653’);
document.write(ms);