正则表达式模式C＃

Question

I have the following string that would require me to parse it via Regex in C#.

Format: rec_mnd.rate.current_rate.sum. QWD.RET : 214345

I would like to extract our the bold chars as group objects in a groupcollection.

QWD = 1 group RET = 1 group 214345 = 1 group

what would the message pattern be like?

Answer 1

It would be something like this:

string s = "Format: rec_mnd.rate.current_rate.sum.QWD.RET : 214345";
Match m = Regex.Match(s, @"^Format: rec_mnd\.rate\.current_rate\.sum\.(.+?)\.(.+?) : (\d+)$");
if( m.Success )
{
    Console.WriteLine(m.Groups[1].Value);
    Console.WriteLine(m.Groups[2].Value);
    Console.WriteLine(m.Groups[3].Value);
}

The question mark in the first two groups make that quantifier lazy: it will capture the least possible amount of characters. In other words, it captures until the first . it sees. Alternatively, you could use ([^.]+) in those groups, which explicitly captures everything except a period.

The last group explicitly only captures decimal digits. If your expression can have other values on the right side of the : you'd have to change that to .+ as well.

Answer 2

Please, make it a lot easier on yourself and label your groups to make it easier to understand what is going on in code.

RegEx myRegex = new Regex(@"rec_mnd\.rate\.current_rate\.sum\.(?<code>[A-Z]{3})\.(?<subCode>[A-Z]{3})\s*:\s*(?<number>\d+)");

var matches = myRegex.Matches(sourceString);
foreach(Match match in matches)
{
    //do stuff
    Console.WriteLine("Match");
    Console.WriteLine("Code:    " + match.Groups["code"].Value);
    Console.WriteLine("SubCode: " + match.Groups["subCode"].Value);
    Console.WriteLine("Number:  " + match.Groups["number"].Value);
}

Answer 3

不管。之间是什么，这都应该为您提供所需的内容。

@"(?:.+\.){4}(.\w+)\.(\w+)\s?:\s?(\d+)"