How to convert javascript timestamp to date format _ javascript skills

This article describes how to convert a js timestamp to a date format. If you are interested, refer to the Unix timestamp: Unix timestamp ), or Unix time or POSIX time is a time representation, it is defined as the total number of seconds from GMT, January 1, January 01, 1970 to the present. Unix timestamps are not only used in Unix and Unix-like systems, but also widely used in many other operating systems.

Currently, a considerable number of operating systems use 32-bit binary numbers to represent the time. The Unix timestamp of such systems can be used up to GMT, January 1, January 19, 2038 (Binary: 01111111 11111111 11111111 11111111 ). In the next second, the binary number will change to 10000000 00000000 00000000 00000000. An overflow error occurs, causing the system to misunderstand the time as December 13, 1901. This may cause software faults or even system paralysis. Systems that use 64-bit binary numbers to represent time (a maximum of 292,277,026,596 seconds from January 1, December 04 to GMT) will not experience such overflow issues.

1. js converts time to Timestamp
1. js method for getting the current Timestamp

var timestamp1 = Date.parse (new Date ());
var timestamp2 = (new Date ()). valueOf ();
var timestamp3 = new Date (). getTime ();
The first type: the obtained timestamp is changed from milliseconds to 000 to display, and the second and third types are obtained the current millisecond timestamp.

2.js Get the method of making timestamp

var oldTime = (new Date ("2015/06/23 08:00:20")). getTime () / 1000;
The unit of the value returned by getTime () is milliseconds.

2.js converts the timestamp to a common date format
1.Date to LocaleString method

function getLocalTime (nS) {
 return new Date (parseInt (nS) * 1000) .toLocaleString (). replace (/: \ d {1,2} $ /, '');
}
The parseInt () function can parse a string and return an integer.

The time operation unit in js is milliseconds.

The toLocaleString () method converts Date objects to strings based on local time, and returns the result.

The replace () method is used to replace some characters with some characters in a string, or to replace a substring that matches a regular expression.

replace (/: \ d {1,2} $ /, '') Verify that the replacement is: the end string with one or two digits at the beginning, which is seconds; the replacement is empty

The display is as follows:

So we can use regular expressions to change the date format we want.

2.Date property method

function add0 (m) {return m <10? '0' + m: m}
function format (shijianchuo)
{
// shijianchuo is an integer, otherwise parseInt conversion
var time = new Date (shijianchuo);
var y = time.getFullYear ();
var m = time.getMonth () + 1;
var d = time.getDate ();
var h = time.getHours ();
var mm = time.getMinutes ();
var s = time.getSeconds ();
return y + '-' + add0 (m) + '-' + add0 (d) + '' + add0 (h) + ':' + add0 (mm) + ':' + add0 (s);
}
3. Encapsulated time formatter

/ **
 * Same timestamp formatting function as PHP
 * @param {string} format
 * @param {int} timestamp The time to be formatted The default is the current time
 * @return {string} formatted time string
 * /
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 () {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 fY () + "-" + fm () + "-" + fd () + "T" + fh () + ":" + fi () + ":" + fs () + fP ()},
  // 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;
  });
}
The calling method can easily convert the timestamp into a date format, such as:

date ('Y-m-d', '1350052653'); // It is convenient to convert the timestamp to 2012-10-11
date ('Y-m-d H: i: s', '1350052653'); // The result is 2012-10-12 22:37:33
The above is the method of converting js timestamp to date format, I hope it will be helpful for everyone's learning.