Combine contents of two files using LINQ to CSV

Question

This is probably a dumb question, but I'm wondering how I would fill a list with the following data for a CSV file.

Here's the code so far,

class Info
{
    [CsvColumn(Name = "Lease Name", FieldIndex = 1)]
    public string leaseName2 { get; set; }

    [CsvColumn(Name = "Field Name", FieldIndex = 2)]
    public string fieldName2 { get; set; }

    [CsvColumn(Name = "Reservoir", FieldIndex = 3)]
    public string reservoir2 { get; set; }

    [CsvColumn(Name = "Operator", FieldIndex = 4)]
    public string operator2 { get; set; }

    [CsvColumn(Name = "County", FieldIndex = 5)]
    public string county2 { get; set; }

    [CsvColumn(Name = "State", FieldIndex = 6)]
    public string state2 { get; set; }

    [CsvColumn(Name = "Majo", FieldIndex = 7)]
    public string majo2 { get; set; }

    [CsvColumn(Name = "Resv Cat", FieldIndex = 8)]
    public string resvCat2 { get; set; }

    [CsvColumn(Name = "Discount Rate", FieldIndex = 9)]
    public double disRate2 { get; set; }

There are more columns I just did not want to list them all because that would be redundant. If anyone could help that would be greatly appreciated.

It's not clear what you're asking. Are you wanting to take the contents of a CSV file and put it into a `List`? — neontapir, May 30 '13 at 21:06
Or, are you wanting the reverse: http://stackoverflow.com/questions/2306667/how-can-i-convert-a-list-of-objects-to-csv — neontapir, May 30 '13 at 21:07
@neontapir Sorry, I have two files that are being merged and I want the contents of that file to go into a list with these so I could create a CSV file — Stock, May 30 '13 at 21:16

neontapir · Accepted Answer · 2013-05-30T21:35:04.720

@GertArnold is right, you can use Union(). I used Concat() in my example. Union returns distinct records, Concat doesn't.

using System;
using System.Collections.Generic;
using System.Linq;
using LINQtoCSV;

namespace LinqCsvSandbox
{
class SampleData
{
    [CsvColumn(Name = "ID", FieldIndex = 1)]
    public string ID { get; set; }

    [CsvColumn(Name = "PersonName", FieldIndex = 2)]
    public string Name { get; set; }

    public override string ToString()
    {
        return string.Format("{0}: {1}", ID, Name);
    }
}

class Program
{
    static void Main(string[] args)
    {           
        var inputFileDescription = new CsvFileDescription
        {
            SeparatorChar = ',', 
            FirstLineHasColumnNames = false,
            FileCultureName = "en-us",
            EnforceCsvColumnAttribute = true,
        };

        CsvContext cc = new CsvContext();

        IEnumerable<SampleData> data1 = cc.Read<SampleData>("File1.csv", inputFileDescription);
        IEnumerable<SampleData> data2 = cc.Read<SampleData>("File2.csv", inputFileDescription);

        IEnumerable<SampleData> all = data1.Concat(data2);

        // Uncomment to see the items printed
        //foreach(var item in all)
        //  Console.WriteLine(item);

        cc.Write(all, "All.csv");           
    }
}
}

In my example, File1.csv contains

1,Fred
2,Wilma

File2.csv contains

3,Tango
4,Cash

And the resulting All.csv contains

ID,PersonName
1,Fred
2,Wilma
3,Tango
4,Cash

For those unfamiliar, Linq to CSV is available as a package from NuGet.

Thank you, this is very helpful! Instead of the data1 and data2 being .csv files could they also be .txt files and work the same way? — Stock, May 30 '13 at 21:41

score 0 · Answer 2 · answered May 30 '13 at 21:29

Here are a couple of ways, the first is just using an object initializer, the second transfers a small list to the your CSV list:

List<Info> infoList = new List<Info>
        {
            new Info()
            {
                leaseName2 = "x"
            }

        };

    List<string> stringList = new List<string> {"xy", "zz"};

    infoList.AddRange(stringList.Select(stringVal => new Info()
        {
            leaseName2 = stringVal
        }));

Combine contents of two files using LINQ to CSV

2 Answers2