我想使用当前日期生成随机数？ [英] i want to generate random number using current date ?

问题描述

我想按顺序生成一个随机数，包括当前日期+六位数序列号。



例如20141003 + 000001，最后一个数字将改变每个日期......！



例如：



20141003 + 000001,20141003 + 000002 ... .....

20141004 + 000001,20141004 + 000002 ........

20141005 + 000001,20141005 + 000002 ....... 。





如何在c＃中实现它？

i want to generate a random number in sequence include current date + six digit sequence number.

for example 20141003 + 000001 and the last number will change will the every date...!

example :

20141003 + 000001, 20141003 + 000002........
20141004 + 000001 ,20141004 + 000002........
20141005 + 000001 ,20141005 + 000002........


how can i implement it in c# ?

推荐答案

我们无法具体回答：这取决于您如何存储信息。

如果您使用的是数据库，那么有一套方法，如果这些是文件名，那么还有另外一种 - 依此类推。

因为你是一个每日序列号，您需要分别存储前一个值或日期和序列号 - 以及如何生成下一个值取决于整个系统的使用方式。如果这是一个单一的用户系统，那么这是一项微不足道的任务 - 但对于多用户环境来说，它要复杂得多，因为你必须阻止两个独立的进程生成相同的值。



但是仍然适用一些通用规则：

1）永远不要预先计算值：只有在提交记录，文件或其他内容时才分配它。不要试图说我的下一个号码将是'dddddnnnnn'所以我会使用它 - 它会在某些时候给你带来悲伤

2）如果有疑问，假设你会使用它作为多用户。它更复杂，但实现和测试起来要比以后添加容易得多。

3）如果可能，利用环境提供的设施：数据库（相对）用于此并且可以使事情变得更容易因此，如果您使用的是数据库，请不要依赖于以电子方式实现的手动系统。

We can't specifically answer that: it depends on how you are storing information.
If you are using a database, then there are one set of ways, if these are for filenames, then there is another - and so on.
Because you was a daily sequence number, you need to store either the previous value or a "date" and "sequence number" separately - and how you generate the "next" value depends on how your whole system is used. If this is a single user system, then it's a trivial task - but for a multiuser environment it's a lot more complex as you have to prevent two separate processes from generating the same value.

But some general rules apply anyway:
1) Never "Precalculate" the value: only ever assign it when you commit a record, or file or whatever. Do not try to say "my next number will be 'dddddnnnnn' so I'll use that" - it will always give you grief at some point
2) If in doubt, assume that you will be using this as multiuser. It's more complex, but a lot easier to implement and test to start with than to add later.
3) If possible, take advantages of facilities provided by the environment: databases are (relatively) used to this and can make things easier. So if you are using a database, don't rely on a "manual system" implemented electronically.

从技术上讲，这不是随机数。如果将最后生成的 date 和序列号存储在持久存储中，则可以轻松生成它们（例如文件，数据库）。然后

• 如果日期改变，请使用新日期并重置序列号。

Technically that aren't a random numbers. You may easily generate them if you store both the date and sequence number of the last generated one in a persistent storage (e.g. file, database). Then

• if date changed, use the new date and reset the sequence number.

• 如果日期相同，则使用此日期并增加序列号。

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