http://lihao312.iteye.com/blog/1938815

(function (factory) {  
  if (typeof define === 'function' && define.amd) {  
    // AMD. Register as an anonymous module.  
    define(['jquery'], factory);  
  } else {  
    // Browser globals  
    factory(jQuery);  
  }  
}(function ($) {  
  $.timeago = function(timestamp) {  
    if (timestamp instanceof Date) {  
      return inWords(timestamp);  
    } else if (typeof timestamp === "string") {  
      return inWords($.timeago.parse(timestamp));  
    } else if (typeof timestamp === "number") {  
      return inWords(new Date(timestamp));  
    } else {  
      return inWords($.timeago.datetime(timestamp));  
    }  
  };  
  var $t = $.timeago;  
  
  $.extend($.timeago, {  
    settings: {  
      refreshMillis: 60000,  
      allowFuture: false,  
      localeTitle: false,  
      cutoff: 0,  
      strings: {  
        prefixAgo: null,  
        prefixFromNow: null,  
        suffixAgo: "前",  
        suffixFromNow: "from now",  
        seconds: "1分钟",  
        minute: "1分钟",  
        minutes: "%d分钟",  
        hour: "1小时",  
        hours: "%d小时",  
        day: "1天",  
        days: "%d天",  
        month: "1月",  
        months: "%d月",  
        year: "1年",  
        years: "%d年",  
        wordSeparator: "",  
        numbers: []  
      }  
    },  
    inWords: function(distanceMillis) {  
      var $l = this.settings.strings;  
      var prefix = $l.prefixAgo;  
      var suffix = $l.suffixAgo;  
      if (this.settings.allowFuture) {  
        if (distanceMillis < 0) {  
          prefix = $l.prefixFromNow;  
          suffix = $l.suffixFromNow;  
        }  
      }  
  
      var seconds = Math.abs(distanceMillis) / 1000;  
      var minutes = seconds / 60;  
      var hours = minutes / 60;  
      var days = hours / 24;  
      var years = days / 365;  
  
      function substitute(stringOrFunction, number) {  
        var string = $.isFunction(stringOrFunction) ? stringOrFunction(number, distanceMillis) : stringOrFunction;  
        var value = ($l.numbers && $l.numbers[number]) || number;  
        return string.replace(/%d/i, value);  
      }  
  
      var words = seconds < 45 && substitute($l.seconds, Math.round(seconds)) ||  
        seconds < 90 && substitute($l.minute, 1) ||  
        minutes < 45 && substitute($l.minutes, Math.round(minutes)) ||  
        minutes < 90 && substitute($l.hour, 1) ||  
        hours < 24 && substitute($l.hours, Math.round(hours)) ||  
        hours < 42 && substitute($l.day, 1) ||  
        days < 30 && substitute($l.days, Math.round(days)) ||  
        days < 45 && substitute($l.month, 1) ||  
        days < 365 && substitute($l.months, Math.round(days / 30)) ||  
        years < 1.5 && substitute($l.year, 1) ||  
        substitute($l.years, Math.round(years));  
  
      var separator = $l.wordSeparator || "";  
      if ($l.wordSeparator === undefined) { separator = " "; }  
      return $.trim([prefix, words, suffix].join(separator));  
    },  
    parse: function(iso8601) {  
      var s = $.trim(iso8601);  
      s = s.replace(/\.\d+/,""); // remove milliseconds  
      s = s.replace(/-/,"/").replace(/-/,"/");  
      s = s.replace(/T/," ").replace(/Z/," UTC");  
      s = s.replace(/([\+\-]\d\d)\:?(\d\d)/," $1$2"); // -04:00 -> -0400  
      return new Date(s);  
    },  
    datetime: function(elem) {  
      var iso8601 = $t.isTime(elem) ? $(elem).attr("datetime") : $(elem).attr("title");  
      return $t.parse(iso8601);  
    },  
    isTime: function(elem) {  
      // jQuery's `is()` doesn't play well with HTML5 in IE  
      return $(elem).get(0).tagName.toLowerCase() === "time"; // $(elem).is("time");  
    }  
  });  
  
  // functions that can be called via $(el).timeago('action')  
  // init is default when no action is given  
  // functions are called with context of a single element  
  var functions = {  
    init: function(){  
      var refresh_el = $.proxy(refresh, this);  
      refresh_el();  
      var $s = $t.settings;  
      if ($s.refreshMillis > 0) {  
        setInterval(refresh_el, $s.refreshMillis);  
      }  
    },  
    update: function(time){  
      $(this).data('timeago', { datetime: $t.parse(time) });  
      refresh.apply(this);  
    },  
    updateFromDOM: function(){  
      $(this).data('timeago', { datetime: $t.parse( $t.isTime(this) ? $(this).attr("datetime") : $(this).attr("title") ) });  
      refresh.apply(this);  
    }  
  };  
  
  $.fn.timeago = function(action, options) {  
    var fn = action ? functions[action] : functions.init;  
    if(!fn){  
      throw new Error("Unknown function name '"+ action +"' for timeago");  
    }  
    // each over objects here and call the requested function  
    this.each(function(){  
      fn.call(this, options);  
    });  
    return this;  
  };  
  
  function refresh() {  
    var data = prepareData(this);  
    var $s = $t.settings;  
  
    if (!isNaN(data.datetime)) {  
      if ( $s.cutoff == 0 || distance(data.datetime) < $s.cutoff) {  
        $(this).text(inWords(data.datetime));  
      }  
    }  
    return this;  
  }  
  
  function prepareData(element) {  
    element = $(element);  
    if (!element.data("timeago")) {  
      element.data("timeago", { datetime: $t.datetime(element) });  
      var text = $.trim(element.text());  
      if ($t.settings.localeTitle) {  
        element.attr("title", element.data('timeago').datetime.toLocaleString());  
      } else if (text.length > 0 && !($t.isTime(element) && element.attr("title"))) {  
        element.attr("title", text);  
      }  
    }  
    return element.data("timeago");  
  }  
  
  function inWords(date) {  
    return $t.inWords(distance(date));  
  }  
  
  function distance(date) {  
    return (new Date().getTime() - date.getTime());  
  }  
  
  // fix for IE6 suckage  
  document.createElement("abbr");  
  document.createElement("time");  
}));