Creating CSV with many columns from a list of objects

Question

I am trying to use the following code to generate CSV file:

public static IEnumerable<string> ToCsv<T>(IEnumerable<T> objectlist
    , string separator = ",", bool header = true)
{
    FieldInfo[] fields = typeof(T).GetFields();
    PropertyInfo[] properties = typeof(T).GetProperties();
    if (header)
    {
        yield return String.Join(separator, fields                
                .Select(f => f.Name)
                .Concat(properties.Select(p => p.Name))
                .ToArray()); 
    }
    foreach (var o in objectlist)
    {
        yield return string.Join(separator, fields
            .Select(f=>(f.GetValue(o) ?? "")
            .ToString())
            .Concat(properties
            .Select(p=>(p.GetValue(o,null) ?? "").ToString())).ToArray());
    }
}

And to produce the CSV file:

public class Person
{
    public int IdPerson { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
}

var persons = new List<Person>
{
    new Person(){IdPerson=1, FirstName = "FirstName, 1", LastName = "LastName 1" },
    new Person(){IdPerson=2, FirstName = "FirstName/ 2", LastName = "LastName 2" },
    new Person(){IdPerson=3, FirstName = "FirstName 3", LastName = "LastName 3" },
};

using (TextWriter tw = File.CreateText(@"D:\testoutput.csv"))
{
   foreach (var line in ExcelExport.ToCsv(persons))
   {
       tw.WriteLine(line);
   }                
}

However, all my data nested in one column:

How is it possible to put the above data in different columns?

Ashkan Mobayen Khiabani · Accepted Answer · 2019-03-15T20:33:21.890

3

Nothing is wrong with your csv, just excel does not recognize comma as separator. add this line as the first line of your csv file:

sep=,

and it will work fine.

Also, note that you have to wrap each item between double quotes to escape possible commas inside it and replace any double quote (inside text) with 2 double quotes to scape possible double quotes in the text:

yield return String.Join(separator, 
            fields.Select(f => $"\"{f.Name.Replace("\"","\"\"")}\"")
            .Concat(properties.Select(p=>p.Name)).ToArray());

edited Mar 15 '19 at 20:33

answered Mar 15 '19 at 20:29

Ashkan Mobayen Khiabani

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Man, thank you very much! I will accept your answer in 8 minutes!:) – StepUp Mar 15 '19 at 20:33
@StepUp you are welcome. Please have a look at my edited answer – Ashkan Mobayen Khiabani Mar 15 '19 at 20:34
1

Your rep shows that you are an experienced coder, just pay attention to the scaping I mentioned, because I have learned it the hard way ;) – Ashkan Mobayen Khiabani Mar 15 '19 at 20:49

Creating CSV with many columns from a list of objects

1 Answers1