Regex.Replace just part of regex

Question

I made this line of code

mystring= Regex.Replace(mystring, @"\d+IEME", "E"); 

But got a problem because I want to keep the number. Like 7IEME replace to 7E

Answer 1

用一个组捕获\\d+ ，然后替换，使用$1表示“ Group 1”，后跟E

mystring= Regex.Replace(mystring, @"(\d+)IEME", "$1E"); 

Answer 2

You should be using groups:

string mystring = "7IEME";
mystring= Regex.Replace(mystring, @"(\d+)IEME", "$1E");