C＃中的特定正则表达式

Question

Can someone enlighten me on why the folloewing regex does not work in C#? Thank you.

Regex 101

Im trying to get raudi06 out of the following string (as explained in link): "\\n http://dsde.innogamescdn.com/8.30.1/23852/graphic/welcome/player_points.png?3ba0c\\">\\n raudi06\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t"

Here comes the code:

        Match match = new Regex(@"[^>]+>\\n\s+(.*?)\\").Match(playerText);
        return match.Groups[1].Value;

The value is an empty string, as opposed to the regex explanation on regex101.com. Is this due to C# regex flavor? I don't know much about regex and hope that maybe you know about these specific details.

Thank you in advance!

Answer 1

In fact the whitespace characters (\\n, \\t) were not literal. I found out about that by right clicking the variable in the watch window of Visual Studio and selecting the value option, which displayed the string without the literal whitespace characters.

[^>]+>\s+([^\s]*)

Does work to match the string. Thank you for your hint, Avinash Raj.

Answer 2

尝试以下一项：

System.Text.RegularExpressions.Regex.Match(input, "[^>]+>\s+(.*?)\s", System.Text.RegularExpressions.RegexOptions.Multiline)

Answer 3

When you see the \\n and the \\t in your string, they are just single caracter placeholders for newline and tab. This means that you will never find \\n by looking for a \\ and a n.

The pattern you're using will look specifically for a backslash followed by the literal n. To change this, simply remove one of the backslashes, leaving \\n instead of \\n

The next challenge is the end criteria for your string. In your pattern you're looking for a backslash again (\\), but there is none, just tabs (\\t). This one you could change to \\t and it should work.

Match match = new Regex(@"[^>]+>\n\s+(.*?)\t").Match(playerText);