Pattern matching problem in C#

Question

I have a string like "AAA 101 B202 C 303 " and I want to get rid of the space between char and number if there is any. So after operation, the string should be like "AAA101 B202 C303 ". But I am not sure whether regex could do this?

Any help? Thanks in advance.

Answer 1

Yes, you can do this with regular expressions. Here's a short but complete example:

using System;
using System.Text.RegularExpressions;

class Test
{
    static void Main()
    {
        string text = "A 101 B202 C 303 ";
        string output = Regex.Replace(text, @"(\p{L}) (\d)", @"$1$2");
        Console.WriteLine(output); // Prints A101 B202 C303
    }
}

(If you're going to do this a lot, you may well want to compile a regular expression for the pattern.)

The \p{L} matches any unicode letter - you may want to be more restrictive.

Answer 2

You can do something like

([A-Z]+)\s?(\d+)

And replace with

$1$2

The expression can be tightened up, but the above should work for your example input string.

What it does is declaring a group containing letters (first set of parantheses), then an optional space (\s?), and then a group of digits (\d+). The groups can be used in the replacement by referring to their index, so when you want to get rid of the space, just replace with $1$2.