Get number of skipped blank lines when using CsvHelper?

Question

When you've configured a CsvReader with a configuration to skip empty lines by using IgnoreBlankLines property of CsvConfiguration, how can I go about at getting the count of the skipped lines?

Alternatively, if I don't skip them - how do I track them?

It seems that a blank line is represented by the first field having an empty string as value, and then every other field having null - but this is an implementation detail - i.e, it could be possible that actual data came in this format, or am I wrong?

Answer 1

If your file has a header, you could read the header and then get the row number you are on. The following example skips two lines so the row is 3 when the header is read.

void Main()
{
    var config = new CsvConfiguration(CultureInfo.InvariantCulture)
    {
        IgnoreBlankLines = true
    };
    
    using (var reader = new StringReader("\n\nId,Name\n1,One"))
    using (var csv = new CsvReader(reader, config))
    {
        csv.Read();
        csv.ReadHeader();
        
        var firstRow = csv.Context.Parser.Row;
        
        var records = csv.GetRecords<Foo>();
        
        Console.WriteLine(firstRow); // 3
    }
}

public class Foo
{
    public int Id { get; set; }
    public string Name { get; set; }
}

Getting the row number without a header would be only slightly more complicated.

void Main()
{
    var config = new CsvConfiguration(CultureInfo.InvariantCulture)
    {
        IgnoreBlankLines = true,
        HasHeaderRecord = false
    };
    
    using (var reader = new StringReader("\n\n1,One"))
    using (var csv = new CsvReader(reader, config))
    {
        var isFirstRow = true;
        var firstRow = 0;
        var records = new List<Foo>();
        
        while (csv.Read())
        {
            if (isFirstRow)
            {
                firstRow = csv.Context.Parser.Row;
                isFirstRow = false;
            }
            records.Add(csv.GetRecord<Foo>());
        }
        Console.WriteLine(firstRow); // 3
    }
}

public class Foo
{
    public int Id { get; set; }
    public string Name { get; set; }
}