用C＃和正则表达式替换模式之间的char

Question

I'm trying to improve a code using RegEx. Basically I have some patterns and I need to replace with the same pattern but using uppercase.

For example:

".a."

to

".A."

another pattern

"'a"

to

"'A"

I know a little bit about regex, but I don't know to replace to the same content but on uppercase.

Answer 1

As Cyral said:

var str = "hello.a.world";
str = Regex.Replace(str, @'\.[a-z]\.', x => x.Value.ToUpper());
//str == "hello.A.world"

This tutorial is a great reference for .NET's regular expression engine and regular expressions in general.

Expresso is a fantastic tool that I use frequently when I work with regular expressions. It will spell out what the regular expression does, and allows you to test it out on sample text. It also uses the same regex engine as .NET, so if your expression works in Expresso, it will work in C#.

Edit: Just to be clear, Cyral's answer is correct, I just wanted to be sure to add these links on to the page, as they are very helpful.

Answer 2

You don't need to use regex, you can just use String.ToUpper

string str = ".a.";
str = str.ToUpper();

EDIT: To replace only from a pattern, run a function on the match: (Where [az] is your own regex)

str = Regex.Replace(str, @"[a-z]", s => s.Value.ToUpper());