日期

1-js/05-data-types/10-date/1-new-date/solution.md

@@ -1,6 +1,6 @@
-The `new Date` constructor uses the local time zone by default. So the only important thing to remember is that months start from zero.
+`new Date` 构造函数默认使用当地时区。所以唯一需要牢记的是月份从 0 开始计数。
 
-So February has number 1.
+所以二月对应的数值是 1。
 
 ```js run
 let d = new Date(2012, 1, 20, 3, 12);

1-js/05-data-types/10-date/1-new-date/task.md

@@ -2,8 +2,8 @@ importance: 5
 
 ---
 
-# Create a date
+# 创建日期
 
-Create a `Date` object for the date: Feb 20, 2012, 3:12am. The time zone is local.
+创建一个 `Date` 对象，日期是：Feb 20, 2012, 3:12am。时区是当地时区。
 
-Show it using `alert`.
+使用 `alert` 显示结果。

1-js/05-data-types/10-date/2-get-week-day/solution.md

@@ -1,6 +1,6 @@
-The method `date.getDay()` returns the number of the weekday, starting from sunday.
+`date.getDay()` 方法返回星期数，从星期日开始。
 
-Let's make an array of weekdays, so that we can get the proper day name by its number:
+我们创建一个星期数组，这样可以通过它的序号得到名称：
 
 ```js run
 function getWeekDay(date) {

1-js/05-data-types/10-date/2-get-week-day/task.md

@@ -2,13 +2,13 @@ importance: 5
 
 ---
 
-# Show a weekday
+# 展示星期数
 
-Write a function `getWeekDay(date)` to show the weekday in short format: 'MO', 'TU', 'WE', 'TH', 'FR', 'SA', 'SU'.
+写一个函数 `getWeekDay(date)` 来显示一个日期的星期数，用简写表示：'MO'、'TU'、'WE'、'TH'、'FR'、'SA'、'SU'。
 
-For instance:
+举个例子
 
 ```js no-beautify
 let date = new Date(2012, 0, 3);  // 3 Jan 2012
-alert( getWeekDay(date) );        // should output "TU"
+alert( getWeekDay(date) );        // 应该输出 "TU"
 ```

1-js/05-data-types/10-date/3-weekday/solution.md

@@ -3,7 +3,7 @@ function getLocalDay(date) {
 
   let day = date.getDay();
 
-  if (day == 0) { // 0 becomes 7
+  if (day == 0) { // 0，改为 7
     day = 7;
   }
 

1-js/05-data-types/10-date/3-weekday/task.md

@@ -2,11 +2,11 @@ importance: 5
 
 ---
 
-# European weekday
+# 欧洲的星期表示方法
 
-European countries have days of week starting with monday (number 1), then tuesday (number 2) and till sunday (number 7). Write a function `getLocalDay(date)` that returns the "european" day of week for `date`.
+欧洲国家的星期计算是从星期一（数字 1）开始，然后星期二（数字 2），直到星期日（数字 7）。写一个函数 `getLocalDay(date)`，返回日期的欧洲式星期数。
 
 ```js no-beautify
 let date = new Date(2012, 0, 3);  // 3 Jan 2012
-alert( getLocalDay(date) );       // tuesday, should show 2
+alert( getLocalDay(date) );       // 星期二，应该返回 2
 ```

1-js/05-data-types/10-date/4-get-date-ago/solution.md

@@ -1,4 +1,4 @@
-The idea is simple: to substract given number of days from `date`:
+思路很简单：从 `date` 中减去给定的天数：
 
 ```js
 function getDateAgo(date, days) {
@@ -7,9 +7,9 @@ function getDateAgo(date, days) {
 }
 ```
 
-...But the function should not change `date`. That's an important thing, because the outer code which gives us the date does not expect it to change.
+...但是函数不能修改 `date`。这一点很重要，因为外部环境不希望它被修改。
 
-To implement it let's clone the date, like this:
+要实现这一点，我们可以复制这个日期，就像这样：
 
 ```js run
 function getDateAgo(date, days) {

1-js/05-data-types/10-date/4-get-date-ago/task.md

@@ -2,13 +2,13 @@ importance: 4
 
 ---
 
-# Which day of month was many days ago?
+# 许多天之前是该月的哪一天？
 
-Create a function `getDateAgo(date, days)` to return the day of month `days` ago from the `date`.
+写一个函数 `getDateAgo(date, days)`，返回特定日期 `date` 往前 `days` 天数后，是当月的哪一天。
 
-For instance, if today is 20th, then `getDateAgo(new Date(), 1)` should be 19th and `getDateAgo(new Date(), 2)` should be 18th.
+举个例子，今天是 20 号，那么 `getDateAgo(new Date(), 1)` 应该是 19 号，`getDateAgo(new Date(), 2)` 应该是 18 号。
 
-Should also work over months/years reliably:
+跨月、年也应该是正确输出：
 
 ```js
 let date = new Date(2015, 0, 2);
@@ -18,4 +18,4 @@ alert( getDateAgo(date, 2) ); // 31, (31 Dec 2014)
 alert( getDateAgo(date, 365) ); // 2, (2 Jan 2014)
 ```
 
-P.S. The function should not modify the given `date`.
+另：函数不能修改给定的 `date` 值。

1-js/05-data-types/10-date/5-last-day-of-month/task.md

@@ -2,13 +2,13 @@ importance: 5
 
 ---
 
-# Last day of month?
+# 某月的最后一天？
 
-Write a function `getLastDayOfMonth(year, month)` that returns the last day of month. Sometimes it is 30th, 31st or even 28/29th for Feb.
+写一个函数 `getLastDayOfMonth(year, month)`，返回某月的最后一天，有时候是 30，有时是31，甚至是二月的 28/29。
 
-Parameters:
+参数：
 
-- `year` -- four-digits year, for instance 2012.
-- `month` -- month, from 0 to 11.
+- `year` —— 四位数的年份，比如 2012。
+- `month` —— 月份，从 0 到 11。
 
-For instance, `getLastDayOfMonth(2012, 1) = 29` (leap year, Feb).
+举个例子，`getLastDayOfMonth(2012, 1) = 29`

1-js/05-data-types/10-date/6-get-seconds-today/solution.md

@@ -1,13 +1,13 @@
-To get the number of seconds, we can generate a date using the current day and time 00:00:00, then substract it from "now".
+为获取秒数，我们可以创建一个日期，使用今天的日期和 00:00:00 这个时间，然后当前时间减去该时间。
 
-The difference is the number of milliseconds from the beginning of the day, that we should divide by 1000 to get seconds:
+不同之处在于，这样得到的今天之初的日期是毫秒计算，我们应该除以 1000，得到秒数：
 
 ```js run
 function getSecondsToday() {
   let now = new Date();
 
-  // create an object using the current day/month/year
-  let today = new Date(now.getFullYear(), now.getMonth(), now.getDate());
+  // 创建一个对象，使用当前的 day/month/year
+  let today = new Date(now.getFullYear(), now.getMonth(), now.getDate());
 
   let diff = now - today; // ms difference
   return Math.round(diff / 1000); // make seconds
@@ -16,7 +16,7 @@ function getSecondsToday() {
 alert( getSecondsToday() );
 ```
 
-An alternative solution would be to get hours/minutes/seconds and convert them to seconds:
+另一种解决方法是得到 hours/minutes/seconds，然后把它们转化为秒数：
 
 ```js run
 function getSecondsToday() {

1-js/05-data-types/10-date/6-get-seconds-today/task.md

@@ -2,14 +2,14 @@ importance: 5
 
 ---
 
-# How many seconds has passed today?
+# 今天过去了多少秒？
 
-Write a function `getSecondsToday()` that returns the number of seconds from the beginning of today.
+写一个函数 `getSecondsToday()`，返回今天已经过去了多少秒？
 
-For instance, if now `10:00 am`, and there was no daylight savings shift, then:
+举个例子：如果现在是`10:00 am`，并且没有夏令时转移，那么：
 
 ```js
 getSecondsToday() == 36000 // (3600 * 10)
 ```
 
-The function should work in any day. That is, it should not have a hard-coded value of "today".
+该函数应该在任意一天都能正确运行。那意味着，不应该有一个「今天」这个参数不能有意外值。

1-js/05-data-types/10-date/7-get-seconds-to-tomorrow/solution.md

@@ -1,6 +1,5 @@
-To get the number of milliseconds till tomorrow, we can from "tomorrow 00:00:00" substract the current date.
-
-First, we generate that "tomorrow", and then do it:
+为获取距离明天的毫秒数，我们可以用「第二天 00:00:00」这个对象减去当前的日期。
+首先我们生成「第二天」，然后对它做操作：
 
 ```js run
 function getSecondsToTomorrow() {
@@ -14,7 +13,7 @@ function getSecondsToTomorrow() {
 }
 ```
 
-Alternative solution:
+另一种解法：
 
 ```js run
 function getSecondsToTomorrow() {
@@ -29,4 +28,4 @@ function getSecondsToTomorrow() {
 }
 ```
 
-Please note that many countries have Daylight Savings Time (DST), so there may be days with 23 or 25 hours. We may want to treat such days separately.
+请注意，很多国家有夏令时（DST），因此他们可能一天有 23 小时或者 25 小时。我们对这些天数要区别对待。

1-js/05-data-types/10-date/7-get-seconds-to-tomorrow/task.md

@@ -2,14 +2,14 @@ importance: 5
 
 ---
 
-# How many seconds till tomorrow?
+# 距离明天还有多少秒？
 
-Create a function `getSecondsToTomorrow()` that returns the number of seconds till tomorrow.
+写一个函数 `getSecondsToTomorrow()`，返回距离明天的秒数。
 
-For instance, if now is `23:00`, then:
+举个例子，现在是 `23:00`，那么：
 
 ```js
 getSecondsToTomorrow() == 3600
 ```
 
-P.S. The function should work at any day, the "today" is not hardcoded.
+另：该函数应该能在任意一天运行

1-js/05-data-types/10-date/8-format-date-relative/solution.md

@@ -1,37 +1,37 @@
-To get the time from `date` till now -- let's substract the dates.
+为获取 `date` 距离当前时间的间隔 —— 我们将两个日期相减。
 
 ```js run
 function formatDate(date) {
-  let diff = new Date() - date; // the difference in milliseconds
+  let diff = new Date() - date; // 差值用毫秒表示
 
-  if (diff < 1000) { // less than 1 second
-    return 'right now';
+  if (diff < 1000) { // 少于一秒
+    return 'right now';
   }
 
-  let sec = Math.floor(diff / 1000); // convert diff to seconds
+  let sec = Math.floor(diff / 1000); // 将间隔转化为秒
 
   if (sec < 60) {
     return sec + ' sec. ago';
   }
 
-  let min = Math.floor(diff / 60000); // convert diff to minutes
-  if (min < 60) {
+  let min = Math.floor(diff / 60000); // 将间隔转化为分钟
+  if (min < 60) {
     return min + ' min. ago';
   }
 
-  // format the date
-  // add leading zeroes to single-digit day/month/hours/minutes
+  // 格式化日期
+  // 在单个数值之前加 0 日/月/小时/分钟
   let d = date;
   d = [
     '0' + d.getDate(),
     '0' + (d.getMonth() + 1),
     '' + d.getFullYear(),
     '0' + d.getHours(),
     '0' + d.getMinutes()
-  ].map(component => component.slice(-2)); // take last 2 digits of every component
+  ].map(component => component.slice(-2)); // 得到每个组件的后两位
 
-  // join the components into date
-  return d.slice(0, 3).join('.') + ' ' + d.slice(3).join(':');
+  // 将时间信息和日期组合在一起
+ return d.slice(0, 3).join('.') + ' ' + d.slice(3).join(':');
 }
 
 alert( formatDate(new Date(new Date - 1)) ); // "right now"
@@ -40,11 +40,11 @@ alert( formatDate(new Date(new Date - 30 * 1000)) ); // "30 sec. ago"
 
 alert( formatDate(new Date(new Date - 5 * 60 * 1000)) ); // "5 min. ago"
 
-// yesterday's date like 31.12.2016, 20:00
+// 昨天的日期如： 31.12.2016, 20:00
 alert( formatDate(new Date(new Date - 86400 * 1000)) );
 ```
 
-Alternative solution:
+另一种解法：
 
 ```js run
 function formatDate(date) {
@@ -58,8 +58,8 @@ function formatDate(date) {
   let diffMin = diffSec / 60;
   let diffHour = diffMin / 60;
 
-  // formatting
-  year = year.toString().slice(-2);
+  // 格式化
+  year = year.toString().slice(-2);
   month = month < 10 ? '0' + month : month;
   dayOfMonth = dayOfMonth < 10 ? '0' + dayOfMonth : dayOfMonth;
 

1-js/05-data-types/10-date/8-format-date-relative/task.md

@@ -2,16 +2,16 @@ importance: 4
 
 ---
 
-# Format the relative date
+# 格式化相对日期
 
-Write a function `formatDate(date)` that should format `date` as follows:
+写一个函数 `formatDate(date)`，能够将 `date` 格式化如下：
 
-- If since `date` passed less than 1 second, then `"right now"`.
-- Otherwise, if since `date` passed less than 1 minute, then `"n sec. ago"`.
-- Otherwise, if less than an hour, then `"m min. ago"`.
-- Otherwise, the full date in the format `"DD.MM.YY HH:mm"`. That is: `"day.month.year hours:minutes"`, all in 2-digit format, e.g. `31.12.16 10:00`.
+- 如果 `date` 距离现在少于 1 秒，输出 `"刚刚"`。
+- 否则，如果少于 1 分钟，输出 `"n 秒之前"`。
+- 否则，如果少于 1 小时，输出 `"n 分钟之前"`。
+- 否则，输出完整日期，用格式`"DD.MM.YY HH:mm"`。即：`"day.month.year hours:minutes"`，所有的数都用两位数表示，例如：`31.12.16 10:00`。
 
-For instance:
+举个例子：
 
 ```js
 alert( formatDate(new Date(new Date - 1)) ); // "right now"