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--- javascript:date_format [2016/07/07 20:22] – peter
+++ javascript:date_format [2020/07/15 09:30] (current) – external edit 127.0.0.1
@@ Line 2: / Line 2: @@
 JavaScript provides a bunch of [[http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Date#Methods|methods for getting and setting parts of a date object]], but it lacks a simple way to format dates and times according to a user-specified mask.
+[[http://php.net/date|PHP]]'s date function and ColdFusion's discrete [[http://livedocs.adobe.com/coldfusion/8/htmldocs/functions_c-d_29.html|dateFormat]] and [[http://livedocs.adobe.com/coldfusion/8/htmldocs/functions_t-z_02.html|timeFormat]] functions provide good approaches to follow.
+PHP uses a crazy mix of letters to represent various date entities.  It does offer the advantages that you can apply both date and time formatting with one function, and that none of the special characters overlap.
+ColdFusion on the other hand have conflicting letters where m and mm mean different things depending on whether you're dealing with dates or times. On the other hand, ColdFusion uses very easy to remember special characters for masks.
+With my date formatter, I've tried to take the best features from both, and add some sugar of my own. It did end up a lot like the ColdFusion implementation though, since I've primarily used CF's mask syntax.
 <code javascript>
@@ Line 107: / Line 116: @@
+===== Library =====
+See http://blog.stevenlevithan.com/archives/date-time-format
+<code javascript>
+/*
+ * Date Format 1.2.3
+ * (c) 2007-2009 Steven Levithan <stevenlevithan.com>
+ * MIT license
+ *
+ * Includes enhancements by Scott Trenda <scott.trenda.net>
+ * and Kris Kowal <cixar.com/~kris.kowal/>
+ *
+ * Accepts a date, a mask, or a date and a mask.
+ * Returns a formatted version of the given date.
+ * The date defaults to the current date/time.
+ * The mask defaults to dateFormat.masks.default.
+ */
+var dateFormat = function () {
+  var token = /d{1,4}|m{1,4}|yy(?:yy)?|([HhMsTt])\1?|[LloSZ]|"[^"]*"|'[^']*'/g,
+      timezone = /\b(?:[PMCEA][SDP]T|(?:Pacific|Mountain|Central|Eastern|Atlantic) (?:Standard|Daylight|Prevailing) Time|(?:GMT|UTC)(?:[-+]\d{4})?)\b/g,
+      timezoneClip = /[^-+\dA-Z]/g,
+      pad = function (val, len) {
+              val = String(val);
+              len = len || 2;
+              while (val.length < len) val = "0" + val;
+              return val;
+            };
+  // Regexes and supporting functions are cached through closure
+  return function (date, mask, utc) {
+    var dF = dateFormat;
+    // You can't provide utc if you skip other args (use the "UTC:" mask prefix)
+    if (arguments.length == 1 && Object.prototype.toString.call(date) == "[object String]" && !/\d/.test(date)) {
+      mask = date;
+      date = undefined;
+    }
+    // Passing date through Date applies Date.parse, if necessary
+    date = date ? new Date(date) : new Date;
+    if (isNaN(date)) throw SyntaxError("invalid date");
+    mask = String(dF.masks[mask] || mask || dF.masks["default"]);
+    // Allow setting the utc argument via the mask
+    if (mask.slice(0, 4) == "UTC:") {
+      mask = mask.slice(4);
+      utc = true;
+    }
+    var	_ = utc ? "getUTC" : "get",
+        d = date[_ + "Date"](),
+        D = date[_ + "Day"](),
+        m = date[_ + "Month"](),
+        y = date[_ + "FullYear"](),
+        H = date[_ + "Hours"](),
+        M = date[_ + "Minutes"](),
+        s = date[_ + "Seconds"](),
+        L = date[_ + "Milliseconds"](),
+        o = utc ? 0 : date.getTimezoneOffset(),
+        flags = {
+           d: d,
+          dd: pad(d),
+         ddd: dF.i18n.dayNames[D],
+        dddd: dF.i18n.dayNames[D + 7],
+           m: m + 1,
+          mm: pad(m + 1),
+         mmm: dF.i18n.monthNames[m],
+        mmmm: dF.i18n.monthNames[m + 12],
+          yy: String(y).slice(2),
+        yyyy: y,
+           h: H % 12 || 12,
+          hh: pad(H % 12 || 12),
+           H: H,
+          HH: pad(H),
+           M: M,
+          MM: pad(M),
+           s: s,
+          ss: pad(s),
+           l: pad(L, 3),
+           L: pad(L > 99 ? Math.round(L / 10) : L),
+           t: H < 12 ? "a"  : "p",
+          tt: H < 12 ? "am" : "pm",
+           T: H < 12 ? "A"  : "P",
+          TT: H < 12 ? "AM" : "PM",
+           Z: utc ? "UTC" : (String(date).match(timezone) || [""]).pop().replace(timezoneClip, ""),
+           o: (o > 0 ? "-" : "+") + pad(Math.floor(Math.abs(o) / 60) * 100 + Math.abs(o) % 60, 4),
+           S: ["th", "st", "nd", "rd"][d % 10 > 3 ? 0 : (d % 100 - d % 10 != 10) * d % 10]
+        };
+    return mask.replace(token, function ($0) {
+      return $0 in flags ? flags[$0] : $0.slice(1, $0.length - 1);
+    });
+  };
+}();
+// Some common format strings
+dateFormat.masks = {
+  "default":      "ddd mmm dd yyyy HH:MM:ss",
+  shortDate:      "m/d/yy",
+  mediumDate:     "mmm d, yyyy",
+  longDate:       "mmmm d, yyyy",
+  fullDate:       "dddd, mmmm d, yyyy",
+  shortTime:      "h:MM TT",
+  mediumTime:     "h:MM:ss TT",
+  longTime:       "h:MM:ss TT Z",
+  isoDate:        "yyyy-mm-dd",
+  isoTime:        "HH:MM:ss",
+  isoDateTime:    "yyyy-mm-dd'T'HH:MM:ss",
+  isoUtcDateTime: "UTC:yyyy-mm-dd'T'HH:MM:ss'Z'"
+};
+// Internationalization strings
+dateFormat.i18n = {
+  dayNames: [
+    "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat",
+    "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"
+  ],
+  monthNames: [
+    "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
+    "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"
+  ]
+};
+// For convenience...
+Date.prototype.format = function (mask, utc) {
+  return dateFormat(this, mask, utc);
+};
+</code>
+Note that the day and month names can be changed (for internationalization or other purposes) by updating the **dateFormat.i18n** object.