I have a CSV file that I want to read into a List. Here's an example file:
Plant,Material,"Density, Lb/ft3",Storage Location
FRED,10000477,64.3008,3300
FRED,10000479,6开发者_开发问答2.612,3275
FRED,10000517,90,3550
FRED,10000517,72,3550
FRED,10000532,90,3550
FRED,10000532,72,3550
FRED,10000550,97,3050
I know I can manually read in the CSV file and build the list using a normal StreamReader, but I was wondering if there was a better way, perhaps using LINQ?
You can use a simple code like this, which ignores the header and doesn't work with quotes, but may be sufficient for your needs.
from line in File.ReadAllLines(fileName).Skip(1)
let columns = line.Split(',')
select new
{
Plant = columns[0],
Material = int.Parse(columns[1]),
Density = float.Parse(columns[2]),
StorageLocation = int.Parse(columns[3])
}
Or you can use a library, like others suggested.
For the specific data shown in your question...
var yourData = File.ReadAllLines("yourFile.csv")
.Skip(1)
.Select(x => x.Split(','))
.Select(x => new
{
Plant = x[0],
Material = x[1],
Density = double.Parse(x[2]),
StorageLocation = int.Parse(x[3])
});
If you already have a type declared for your data then you can use that rather than the anonymous type.
Note that this code isn't robust at all. It won't correctly handle values containing commas/newlines etc, quoted string values, or any of the other esoteric stuff that is often found in CSV files.
There's a codeproject for that:
http://www.codeproject.com/KB/linq/LINQtoCSV.aspx
However, you may want to look here:
Linq and streamreader getting lines
I wrote a simple library to allow developers to use LINQ on CSV files. Here is my blog post about it: http://procbits.com/2010/10/11/using-linq-with-csv-files/
In your case, you would have to change your header string to look like this:
Plant,Material,DensityLbft3,StorageLocation
And then you could parse the file like this:
var linqCSV = new CsvToXml("csvfile", true);
linqCsv.TextQualifier = null;
linqCsv.ColumnTypes.Add("Plant", typeof(string));
linqCsv.ColumnTypes.Add("Material", typeof(int));
linqCsv.ColumnTypes.Add("DensityLbft3", typeof(double));
linqCsv.ColumnTypes.Add("StorageLocation", typeof(int));
linqCsv.Convert();
You could then use LINQ like this:
var items = from item in linqCsv.DynamicRecords
where item.Plant == "Fred" && item.DensityLbft3 >= 62.6
orderby item.StorageLocation
select item;
Hope that helps or works for you.
With Cinchoo ETL library, can parse CSV file into objects
Define type matching CSV file structure as below
public class PlantType
{
public string Plant { get; set; }
public int Material { get; set; }
public double Density { get; set; }
public int StorageLocation { get; set; }
}
Load the CSV file
static void LoadCSV()
{
using (var p = new ChoCSVReader<PlantType>("*** YOUR CSV FILE PATH ***")
.WithFirstLineHeader(true)
)
{
foreach (var rec in p)
{
Console.WriteLine(rec.Dump());
}
}
}
It doesn't use LINQ but CsvHelper is a simple method to implement CSV parsing to a .NET object:
using (TextReader txt = new StreamReader(filename))
{
using (var csv = new CsvReader(txt))
{
var records = csv.GetRecords<PlantMaterial>();
return records.ToList();
}
}
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