How to skip some empty rows in csv file and continue reading rows with data? c# console application

Question

I do have have 5 column within my CVS file, the first two columns have 3 empty rows. I would like to skip these empty rows. I know that I have to loop through the file howev

Answer 1

Use a Where clause to keep only rows that are not NullOrWhiteSpace (null, empty or only white spaces):

public static IList<string> ReadFile(string fileName)
{
    return File.ReadAllLines(fileName)
               .Where(line => !string.IsNullOrWhiteSpace(line))
               .ToList();
}

---

After better understanding what you are after for then: For each line use Split to get the different columns and then check that the first 2 are not empty:

public static IList<string> ReadFile(string fileName)
{
    return (from line in File.ReadAllLines(fileName)
            where !string.IsNullOrWhiteSpace(line)
            let columns = line.Split(',')
            where columns.Length >= 2 && 
                !string.IsNullOrWhiteSpace(columns[0]) &&
                !string.IsNullOrWhiteSpace(columns[1])
            select line).ToList();
}

Changed to syntax query just because in my opinion it is cleaer when we start needing things like let

---

If what you want is get all the column values from the file without the empty ones then:

public static IList<string> ReadFile(string fileName)
{
    File.ReadAllLines(fileName)
        .SelectMany(line => line.Split(','))
        .Where(item => !string.IsNullOrWhiteSpace(item))
        .ToList();
}

Answer 2

If you are not familiar/comfortable with Linq then another aproach is like this.

public static IList<string> ReadFile(string fileName)
{
  var results = new List<string>();
  string[] target = File.ReadAllLines(fileName);
  foreach (string line in target)
  {
    var array = line.Split(','); //If your csv is seperated by ; then replace the , with a ;
    if (!string.IsNullOrWhiteSpace(array[0]) && !string.IsNullOrWhiteSpace(array[1]) && array.Length >= 2)
    results.Add(line);
  }
return results;
}

target can still be defined as var, but I've defined it as string[] to make it more obvious that you can then do foreach over the array.

However I like Gilad Green's solution using Linq. I'm less familiar with it so it's not the first solution I think of, but I think it's worth getting familiar with.