Reading Multi-Lines from a Text File

Question

I'm trying to read multi-lines in a text file. It looks like this:

#############################################
B_ATTR 'MILLING_ORIGIN' 'MILLING 0 0.0 0'  3.635 0.405
B_ATTR 'DRILL_ORIGIN' ''  0.0 0.0
B_ATTR 'BOARD_ROUTING_OUTLINE' ''  0.0192 0.0885 0.0862 0.0215 3.84915 0.0215 - 
3.9162 0.0885 3.9162 0.7018 3.8491 0.7689 3.6793 0.7689 3.65335 0.7715 3.6274 0.77935 - 
3.60355 0.7921 3.5826 0.8093 3.5654 0.83025 3.55265 0.8541 3.5448 0.88 3.5422 0.906 - 
3.5422 5.62345 3.54335 5.6408 3.54685 5.6585 3.55265 5.67565 3.56065 5.69185 3.57065 5.7069 - 
3.58255 5.7205 3.59615 5.73245 3.61065 5.7421 3.9162 5.91855 3.9162 6.2136 3.8491 6.2807 - 
0.0862 6.2807 0.0192 6.21365 0.0192 5.91855 0.32465 5.7421 0.33915 5.7324 0.3527 5.72045 - 
0.36465 5.7069 0.3747 5.6919 0.3827 5.67565 0.3885 5.65855 0.39205 5.64085 0.3932 5.62345 - 
0.3932 0.906 0.3906 0.88 0.38275 0.8541 0.37 0.83025 0.3528 0.8093 0.33185 0.7921 - 
0.308 0.77935 0.28205 0.7715 0.2561 0.7689 0.0862 0.7689 0.0192 0.7018
B_ATTR 'BOARD_PLACEMENT_OUTLINE' ''  0.0192 0.0885 0.0862 0.0215 3.84915 0.0215 - 
3.9162 0.0885 3.9162 0.7018 3.8491 0.7689 3.6793 0.7689 3.65335 0.7715 3.6274 0.77935 - 
3.60355 0.7921 3.5826 0.8093 3.5654 0.83025 3.55265 0.8541 3.5448 0.88 3.5422 0.906 - 
3.5422 5.62345 3.54335 5.6408 3.54685 5.6585 3.55265 5.67565 3.56065 5.69185 3

Reading will start with the line that starts with "B_ATTR 'BOARD_ROUTING_OUTLINE'" and end with the line that starts with "B_ATTR 'BOARD_PLACEMENT_OUTLINE'". I wrote this code but it doesn't work. I can't get rid of some spaces.

StreamReader reader = new StreamReader("neutral.txt");

        string lines = reader.ReadToEnd(); //Reading all lines.

        //Takes the lines I want.
        lines = lines.Substring(lines.IndexOf("B_ATTR 'BOARD_ROUTING_OUTLINE'"), lines.IndexOf("B_ATTR 'BOARD_PLACEMENT_OUTLINE'") - lines.IndexOf("B_ATTR 'BOARD_ROUTING_OUTLINE'"));

        //if the line contains "-" , replaces with " "(space).
        while (lines.Contains("-"))
            lines = Regex.Replace(lines, @"\-", " ");

        //if the line contains "  "(two spaces), replaces with " "(one space).
        while (lines.Contains("  "))
            lines = Regex.Replace(lines, @"\  ", " ");

        string[] items = lines.Split(' ');

        List<string> list = new List<string>();

        //Places all of the elements of items to list.
        foreach (var element in items)
            list.Add(element);


        //if the list contains any space , removes it.
        while (list.Contains(" "))
            list.Remove(" ");


        //Removes the elements I don't want.
        list.Remove("B_ATTR");
        list.Remove("'BOARD_ROUTING_OUTLINE'");
        list.Remove("''");
        list.Remove("B_ATTR");
        list.Remove("'BOARD_PLACEMENT_OUTLINE'");           

        string[,] array = new string[50, 2];

        string[] array2 = list.ToArray(); //Turns the list to array.

        int counter = 0;


        //Makes a rectangular array with 50 rows and 2 columns.
        for (int a = 0; a < 50; a++)
            for (int b = 0; b < 2; b++)
            {
                array[a, b] = array2[counter];
                counter++;                    
            }

I actually used regex to get rid of spaces but I can't eliminate the spaces between the lines and those spaces taking place into the array.

Do you have any advice? Am I doing it wrong?

Answer 1

您缺少StreamReader的using语句，但是没有进行更正，我只是将整个文件读取机制替换为；

 string[] lines = File.ReadAllLines("C:\path\to\file.txt");

Answer 2

For operations like this, I prefer to read the file line by line:

while (!reader.EndOfStream)
{
    string line = reader.ReadLine();

    // parse values and add to list
}

You can check the start of the line for your start and end markers, and exit out of the loop when you find the end.

Answer 3

This...

//if the line contains "  "(two spaces), replaces with " "(one space).
while (lines.Contains("  "))
    lines = Regex.Replace(lines, @"\  ", " ");

string[] items = lines.Split(' ');

... can be replaced with ...

string[] items = lines.Split(' ', StringSplitOptions.RemoveEmptyEntries);

... and that should fix your spaces problem.

---

Given that, I would attack this differently and fill an object's properties while reading the file line by line. Here's a little snippet (assuming you only want the routing outline):

var consuming = false;
var routingOutline = new List<decimal>();

Func<string, bool> isDecimal = text =>
    {
        decimal d;
        return decimal.TryParse(text, out d);
    };

foreach (var line in File.ReadLines("data.txt"))
{
    if (line.Contains("BOARD_PLACEMENT_OUTLINE"))
        break;

    if (line.Contains("BOARD_ROUTING_OUTLINE"))
        consuming = true;

    if (consuming)
    {
        var outlineValues = line.Split(' ')
                                .Where(isDecimal)
                                .Select(decimal.Parse);
        routingOutline.AddRange(outlineValues);
    }
}

Answer 4

If you are trying to get rid of all spaces in each array position, you could scrub each index like this:

array[a, b] = Regex.Replace(array2[counter], @"\\s", "");

On a side note, you shouldn't need to escape the spaces and dash in your other regex patterns.