Regular expression to use which matches text before .html and after /

With this string

http://sfsdf.com/sdfsdf-sdfsdf/sdf-as.html

I need to get sdf-as

with this

hellow-1/yo-sdf.html

I need yo-sdf

From stackoverflow

• This should get you want you need:

  Regex re = new Regex(@"/([^/]*)\.html$");
  Match match = re.Match("http://sfsdf.com/sdfsdf-sdfsdf/sdf-as.html");
  Console.WriteLine(match.Groups[1].Value); //Or do whatever you want with the value
  

  This needs using System.Text.RegularExpressions; at the top of the file to work.

  robert : hey Matt S this work perfect many thanks :)

• using System.Text.RegularExpressions;
  Regex pattern = new Regex(".*\/([a-z\-]+)\.html");
  Match match = pattern.Match("http://sfsdf.com/sdfsdf-sdfsdf/sdf-as.html");
  if (match.Success)
  {
      Console.WriteLine(match.Value);
  }
  else
  {
      Console.WriteLine("Not found :(");
  }
  

• Try this:

  string url = "http://sfsdf.com/sdfsdf-sdfsdf/sdf-as.html";
  Match match = Regex.Match(url, @"/([^/]+)\.html$");
  if (match.Success)
  {
      string result = match.Groups[1].Value;
      Console.WriteLine(result);
  }
  

  Result:

  sdf-as
  

  However it would be a better idea to use the System.URI class to parse the string so that you correctly handle things like http://example.com/foo.html?redirect=bar.html.

• This one makes the slash and dot parts optional, and allows the file to have any extension:

  new Regex(@"^(.*/)?(?<fileName>[^/]*?)(\.[^/.]*)?$", RegexOptions.ExplicitCapture);

  But I still prefer Substring(LastIndexOf(...)) because it is far more readable.

• There are many ways to do this. The following uses lookarounds to match only the filename portion. It actually allows no / if such is the case:

  string[] urls = {
     @"http://sfsdf.com/sdfsdf-sdfsdf/sdf-as.html",
     @"hellow-1/yo-sdf.html",
     @"noslash.html",
     @"what-is/this.lol",
  };
  
  foreach (string url in urls) {
     Console.WriteLine("[" + Regex.Match(url, @"(?<=/|^)[^/]*(?=\.html$)") + "]");
  }
  

  This prints:

  [sdf-as]
  [yo-sdf]
  [noslash]
  []
  

  How the pattern works

  There are 3 parts:

  • (?<=/|^) : a positive lookbehind to assert that we're preceded by a slash /, or we're at the beginning of the string
  • [^/]* : match anything but slashes
  • (?=\.html$): a positive lookahead to assert that we're followed by ".html" (literally on the dot)

  References

  • regular-expressions.info/Lookarounds, Anchors

  ---

  A non-regex alternative

  Knowing regex is good, and it can do wonderful things, but you should always know how to do basic string manipulations without it. Here's a non-regex solution:

  static String getFilename(String url, String ext) {
     if (url.EndsWith(ext)) {
       int k = url.LastIndexOf("/");
       return url.Substring(k + 1, url.Length - ext.Length - k - 1);
     } else {
       return "";
     }
  }
  

  Then you'd call it as:

  getFilename(url, ".html")
  

  API links

  • String.Substring, EndsWith, and LastIndexOf

  ---

  Attachments

  • Source code and output on ideone.com