regex - 正则表达式范围 a-Z 中将包含哪些字符？

Question

这个问题在这里已经有了答案:





Is the regular expression [a-Z] valid and if yes then is it the same as [a-zA-Z]?

(7 个回答)


2年前关闭。




如果我有一个正则表达式 [0-Z]或 [a-Z] - 它会匹配哪些字符？它是有效的正则表达式吗？您可以在 0-9 之外的正则表达式中设置范围吗？ , a-z和 A-Z ?

Answer 1

是的，您可以有其他范围。来自 MSDN - Character Classes in Regular Expressions(粗体是我的):

The syntax for specifying a range of characters is as follows:

[firstCharacter-lastCharacter]

where firstCharacter is the character that begins the range and lastCharacter is the character that ends the range. A character range is a contiguous series of characters defined by specifying the first character in the series, a hyphen (-), and then the last character in the series. Two characters are contiguous if they have adjacent Unicode code points.

因此，最终 [0-Z] 将匹配 0123456789:;<=>?ABCDEFGHIJKLMNOPQRSTUVWXYZ 。您可以检查 ASCII table 的 0-Z 。

至于 [a-Z] ，因为它们没有指定连续的系列，所以它们应该不匹配。

请记住，对于一般规则，效果可能是广泛的:Unicode 字符代码，而不仅仅是 ASCII - 当然，最终取决于实现，因此，如果有疑问，请检查它。