.NET中DateTime.Now.ToString的格式化字符串
.NET中DateTime.Now.ToString显示毫秒：
DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff")
DateTime.Now.ToString的其他格式化字符串：
| 格式化字符串 | 释义 | 示例 |
|---|---|---|
| D | long date | Thursday, 10 April 2008 |
| d | short date | 04/10/2008 |
| F | full date long | Thursday, 10 April 2008 06:30:00 |
| f | full date short | Thursday, 10 April 2008 06:30 |
| G | general long | 04/10/2008 06:30:00 |
| g | general short | 04/10/2008 06:30 |
| M | month | April 10 |
| O | ISO 8601 | 2008-04-10T06:30:00.0000000 |
| R | RFC 1123 | Thu, 10 Apr 2008 06:30:00 GMT |
| s | sortable | 2008-04-10T06:30:00 |
| T | long time | 06:30:00 |
| t | short time | 06:30 |
| U | universal full | Wednesday, 09 April 2008 22:30:00 |
| u | universal sortable | 2008-04-10 06:30:00Z |
| Y | year month | 2008 April |
| yy-MM-dd | custom | 08-04-10 |
| yyyy MMMM dd | custom | 2008 April 08 |
| yy-MMMM-dd ddd | custom | 08-Apr-8 Tue |
| yyyy-M-d dddd | custom | 2008-4-8 Tuesday |
| hh:mm:ss t z | custom | 04:03:05 P -7 |
| h:mm:ss tt zz | custom | 4:03:05 PM -07 |
| HH:mm:ss tt zz | custom | 16:03:05 PM -07 |
| HH:m:s tt zzz | custom | 16:3:5 PM -07:00 |
当然也可以使用 DateTime类 提供的属性（如：DateTime.Now.Year）和方法（如：DateTime.Now.ToShortDateString()）。
