How to use Streamreader to read to and from a specific point?

[Robert Hodan]

I'm trying to use the Streamreader function to pull text from a text file and make it into a string, and then place it in a list, and this works just fine for at the start of the line, but I can't figure out how to tell it to extract from a specific keyword, say "key" and end at a certain keyword, say "word" into a string. Can anyone give me a hand?

[Plater]

Probably need to keep reading lines until you fight your start and end words

[Robert Hodan]

I think you may have misunderstood me, I mean how do I do this if I have a line of text like "This is a line of text containing a keyword right in the middle.", how would I get Streamreader to extract the keyword?

[Rabbit]

You can use the IndexOf function to get the start and end points. Then you use the SubString function to pull out that part of the text.

[Jeffrey K Pry]

I am not too familiar with StreamReader but if you can access the BaseStream, you should be able to use BaseStream.seek ...

Try this:

        public static string GetPartOfFile()
        {
            using (var myReader = new StreamReader(@"c:\myFile.txt"))
            {
                myReader.BaseStream.Seek(100, SeekOrigin.Begin);
                string output = myReader.ReadToEnd();
                return output;
            }
        }

[Robert Hodan]

Perhaps this will help.

What I'm working on is a program that reads text files, pulls out any URL's that are in it, and opens it up in the user's default browser if possible, if not, displays them in a nice list. The part that I am working on specifically, is pulling things out from midway in a line. So for example if the line went "Visit us at www.example.com please!" Then all I would want from that is "www.example.co m". If this were to be at the start of a line, it would be quite simple, but I honestly have no clue how to do this if it is in the middle of a line. I figure I need to somehow work with a delimiter, such as a space in this case, then trim the space off. I just don't know how to go about doing that.

The part that I'm working on:

else if(line.Contains("www") == true)
                        {
                            
                            //This is where the read code would go..
                            count++;
                            lineList.Add(midLine);
                        }

This is the entire method, if it helps in any manner.
Hopefully it is explanatory enough..

private void GetLines()
        {
            count = 0;
            //Will run as long as the file is real.
            if (links != null)
            {
                string line;
                StreamReader lines = new StreamReader(links);
                while ((line = lines.ReadLine()) != null)
                {
                    //Makes sure the line isn't blank
                    if (line.Trim().Length != 0)
                    {
                        //Checks to see if the line starts with http
                        if (line.StartsWith("http") == true)
                        {
                            count++;
                            //Adds to the count and adds to the list
                            lineList.Add(line);
                        }
                        else if(line.Contains("www") == true)
                        {
                            
                            //This is where I need help..
                            count++;
                            lineList.Add(midLine);
                        }
                        //Checks to see if the line starts with www
                        if (line.StartsWith("www") == true)
                        {
                            count++;
                            //Adds to the count and adds to the list
                            lineList.Add(line);
                        }
                    }
                }
            }

[Rabbit]

If I were you, I would just use a regular expression in global mode.

[bvrwoo]

use a regular expression for URL format on the the line. If the line is a match but it in your string list or array.

List<string> list = new List<string>();
using(TextReader reader = new StreamReader(/*filename*/)
{
   while (!reader.EndOfStream)
   {
      string line = reader.ReadLine().Trim();
      if (Regex.IsMatch(line, your url pattern, Regex.IgnoreCase))
         list.Add(line);[CODE]

}
}[/CODE]

Another way is to use

List<string>list = new List<string>();
string text = null;
using(TextReader reader = new StreamReader(/*filename*/)
{
   text = reader.ReadToEnd();   
}
if (!string.IsNullOrEmpty(text)
{
   MatchCollection matches = Regex.Matches(text,your url pattern, Regex.IgnoreCase);
  if (matches.Count > 0)
  {     
     foreach(Match m in matches)
     {
        list.Add(text.Substring(m.Index,m.Length));
     }
  }
}