用于检查字符串是否以]，字母和数字开头的正则表达式模式

Question

I'm developing a library with .NET Framework 4.0 and C#.

I want to check if a string begins with this three caracters:

• ]
• One letter (any)
• One number (any)

An example: ]d2

How can I do it using regex?

Answer 1

This regex matches such a string

^\][a-zA-Z][0-9]

• ^ matches start of string
• ] is a special character in regex and needs to be escaped
• [a-zA-Z] matches any letter (any case)
• [0-9] matches a digit. This can be replaced with \\d . It is worth noting that \\d matches digits other than 0 to 9 (like Unicode values corresponding to numerals in other languages)

Answer 2

• ^ - beginning of line
• \\] - the literal character, "]"
• [a-zA-Z] - one letter, az, lower or uppercase
• \\d - one digit

All together: ^\\][a-zA-Z]\\d

I might be slightly off if .NET 4.0 C# regexes aren't exactly as I remember.

Answer 3

在C＃中，代码为：

var result = Regex.Match("]d2", @"^\][a-zA-Z][0-9].*");