如何在C＃Regex中使用“或”，“和”？

I have a pattern to match with the string: string pattern = @"asc" I am checking the SQL SELECT query for right syntax, semantics, ... I need to say that in the end of the query string I can have "asc" or "desc". How can it be written in C#?

我有一个匹配字符串的模式:string pattern = @“asc”我正在检查SQL SELECT查询的正确语法,语义,...我需要说在查询字符串的末尾我可以有“asc “或”desc“。如何用C#编写?

4 个解决方案

#1

That'd look like

那看起来像

new Regex("asc$|desc$").IsMatch(yourQuery)

assuming that you're mandating that asc/desc is the end of the query. You could also do (?:asc|desc)$ which is a little cleaner with the single $, but less readable.

假设您要求asc / desc是查询的结尾。你也可以做(?:asc | desc)$,这对于单个$有点干净,但可读性较差。

#2

You want the "alternation" operator, which is the pipe.

你想要“交替”运算符,这是管道。

For instance, I believe this would be represented as:

例如,我相信这将表示为:

asc|desc

If you want to make it a non-capturing group you can do it in the normal way. I'm not a regex expert, but that's the first thing to try.

如果您想使其成为非捕获组,您可以以正常方式执行此操作。我不是正则表达式专家,但这是第一个尝试的东西。

EDIT: MSDN has a page about regular expression language elements which may help you.

编辑:MSDN有一个关于正则表达式语言元素的页面,可以帮助您。

#3

Just to add to the other answers, you probably wanna apply an ignore case option to the regex as well.

只是为了添加其他答案,您可能还想将一个忽略大小写选项应用于正则表达式。

string tempString = "SELECT * FROM MyTable ORDER BY column DESC";

Regex r = new Regex("asc$|desc$", RegexOptions.CultureInvariant | RegexOptions.IgnoreCase);

bool answer = r.IsMatch(tempString);

#4

I reckon something like the following works as a regex in .Net:

我认为以下作为.Net中的正则表达式:

asc|desc\z

.. it will match end of line as well as end of string. If you just want end of string try:

..它将匹配行尾和字符串结尾。如果你只想结束字符串试试:

asc|desc$

#1