C# Combining lines

Question

Hey everybody, this is what I have going on. I have two text files. Umm lets call one A.txt and B.txt.

A.txt is a config file that contains a bunch of folder names, only 1 listing per folder.

B.txt is a directory listing that contains folders names and sizes. But B contains a bunch of listing not just 1 entry.

What I need is if B, contains A. Take all lines in B that contain A and write it out as A|B|B|B ect....

So example:

A.txt:
Apple
Orange
Pear XBSj
HEROE

B.txt:
Apple|3123123
Apple|3434
Orange|99999999
Orange|1234544
Pear|11
Pear|12
XBSJ|43949
XBSJ|43933

Result.txt:
Apple|3123123|3434
Orange|99999999|1234544
Pear|11|12
XBSJ|43949|43933

This is what I had but it's not really doing what I needed.

string[] combineconfig = File.ReadAllLines(@"C:\a.txt");
        foreach (string ccline in combineconfig)
        {
            string[] readlines = File.ReadAllLines(@"C:\b.txt");
            if (readlines.Contains(ccline))
            {
                foreach (string rdlines in readlines)
                {
                    string[] pslines = rdlines.Split('|');
                    File.AppendAllText(@"C:\result.txt", ccline + '|' + pslines[0]);
                }
            }

I know realize it's not going to find the first "if" because it reads the entire line and cant find it. But i still believe my output file will not contain what I need.

Answer 1

Assuming you're using .NET 3.5 (so can use LINQ), try this:

string[] configLines = File.ReadAllLines("a.txt");
var dataLines = from line in File.ReadAllLines("b.txt")
                let split = line.Split('|')
                select new { Key = split[0], Value = split[1] };
var lookup = dataLines.ToLookup(x => x.Key, x => x.Value);

using (TextWriter writer = File.CreateText("result.txt"))
{
    foreach (string key in configLines)
    {
        string[] values = lookup[key].ToArray();
        if (values.Length > 0)
        {
            writer.WriteLine("{0}|{1}", key, string.Join("|", values));
        }
    }
}

Answer 2

var a = new HashSet<string>(File.ReadAllLines(@"a.txt")
                                .SelectMany(line => line.Split(' ')),
                            StringComparer.CurrentCultureIgnoreCase);

var c = File.ReadAllLines(@"b.txt")
            .Select(line => line.Split('|'))
            .GroupBy(item => item[0], item => item[1])
            .Where(group => a.Contains(group.Key))
            .Select(group => group.Key + "|" + string.Join("|", group.ToArray()))
            .ToArray();

File.WriteAllLines("result.txt", c);

Output:

Apple|3123123|3434
Orange|99999999|1234544
Pear|11|12
XBSJ|43949|43933

Answer 3

you need to enumerate readlines and check if readlines[i].StartsWith(cclines)

Answer 4

This should work:

using System;
using System.Linq;
using System.IO;
using System.Globalization;

namespace SO2593168
{
    class Program
    {
        static void Main(string[] args)
        {
            var a = File.ReadAllLines("A.txt");
            var b =
                (from line in File.ReadAllLines("B.txt")
                 let parts = line.Split('|')
                 select new { key = parts[0], value = parts[1] });

            var comparer = StringComparer.Create(CultureInfo.InvariantCulture, true);
            var result =
                from key in a
                from keyvalue in b
                where comparer.Compare(keyvalue.key, key) == 0
                group keyvalue.value by keyvalue.key into g
                select new { g.Key, values = String.Join("|", g.ToArray()) };

            foreach (var entry in result)
                Console.Out.WriteLine(entry.Key + "|" + entry.values);
        }
    }
}

This produces:

Apple|3123123|3434
Orange|99999999|1234544
Pear|11|12
XBSJ|43949|43933

Code here.

Answer 5

A short one :

var a = File.ReadAllLines("A.txt");
var b = File.ReadAllLines("B.txt");

var query =
    from bline in b
    let parts = bline.Split('|')
    group parts[1] by parts[0] into bg
    join aline in a on bg.Key equals aline
    select aline + "|" + string.Join("|", bg.ToArray());

File.WriteAllLines("result.txt", query.ToArray());