Question

I have a file that looks like this:

STUFF   STUFF       **X**     **Y**  STUFF STUFF
J6      INT-00113G  227.905    5.994  180  SOIC8    
J3      INT-00113G  227.905 -203.244  180  SOIC8     
U13     EXCLUDES    -42.210  181.294  180  QFP128    
U3      IC-00276G     5.135  198.644  90   BGA48     
U12     IC-00270G  -123.610 -201.594  0    SOP8      
J1      INT-00112G  269.665  179.894  180  SOIC16    
J2      INT-00112G  269.665  198.144  180  SOIC16    

And I need to grab the 3rd column and the 4th column seperately and store them into a list in C#.

---

I am currently matching the 3rd and 4th column together using:

        var xyResult = new List<string>();
        var mainResult = new List<string>();

        foreach (var mainLine in fileList)
            mainResult.Add(string.Join(" ", mainLine));

        foreach (var xyLine in mainResult)
        {
            Match xyRegex = Regex.Match(xyLine, @"[\d]+\.[\d]+\s+[\d]+\.[\d]+");

            if (xyRegex.Success)
            {
                xyResult.Add(string.Join(" ", xyRegex));
            }
        }

        List<string> finalXYResult = xyResult.ToList();

        foreach (var line in finalXYResult)
            displayXYRichTextBox.AppendText(line + "\n");

---

Right now I am storing the regex matching both X and Y into one list. I would like to store the two column values seperate. So, one list for X and one list for Y.

---

QUESTION:

• What regex can I use to match the 3rd column of numbers and store it in “X” and also (or seperately using another regex) match the 4th column of numbers and store it in “Y”?

EDIT:

    private void calculateXAndYPlacementTwo()
    {
        // Reads the lines in the file to format.
        var fileReader = File.OpenText(filePath + "\\Calculating X,Y File.txt");

        // Creates a list for the lines to be stored in.
        var fileList = new List<string>();

        // Adds each line in the file to the list.
        while (true)
        {
            var line = fileReader.ReadLine();
            if (line == null)
                break;

            fileList.Add(line);
        }

        // Creates new lists to hold certain matches for each list.
        var xyResult = new List<string>();
        var mainResult = new List<string>();
        var xResult = new List<string>();
        var yResult = new List<string>();

        foreach (var mainLine in fileList)
            mainResult.Add(string.Join(" ", mainLine));

        mainResult.ForEach(xyLine =>
        {
            Match xyRegex = Regex.Match(xyLine, @"(?<x>-?\d+\.\d+)\s+(?<y>-?\d+\.\d+)");
            if (xyRegex.Success)
            {
                String xValue = xyRegex.Groups["x"].Value;
                String yValue = xyRegex.Groups["y"].Value;

                xyResult.Add(String.Join(" ", new[]{ xValue, yValue }));

                foreach (var line in xValue)
                    richTextBox1.AppendText(line + "\n");

                foreach (var line in yValue)
                    richTextBox2.AppendText(line + "\n");
            }
        });
    }

Answer 1

To make things easier I’ve named the groups, but the following should work:

(?<x>-?\d+\.\d+)\s+(?<y>-?\d+\.\d+)

Please note that this requires both the 3rd & 4th column to have decimal numbers (I don’t do any checking to accept either whole or decimal numbers, but if necessary, this can be added).

Note the above has been tested to work.

Summary

Basically we use the capture you had, but extend it using capture groups (the parenthesis). I also use named groups (the ?<x> and ?<y> at the start of the group) so you can reference the values found using xyRegex.Groups["x"] and xyRegex.Groups["y"], respectively.

I also found your capture failed when numbers appeared with negative values, so I added an optional negative symbol (-?) to the pattern to account for that.

So, broken down, here is the statement:

(?<x>              # Begin capture group "x"
  -?                 # allow a negative symbol 0 or 1 time
  \d+                # allow 1+ numbers
  \.                 # allow a single decimal
  \d+                # allow decimal numbers 1+ times
)                  # end capture group "x"
\s+                # allow white space between the number sets
(?<y>              # Begin capture group "y"
  -?                 # \
  \d+                #  | - same as above
  \.                 #  |
  \d+                # /
)                  # End capture group "y"