How to import csv files in C# web application and perform validations checking

Question

How to import csv file in C# web application and perform validations checking .

Please let me know the approach.

Thanks in advance.

Answer 1

Here you go...

        private void loadCsvData(string fileName)
        {
            FileInfo fileIn = new FileInfo(fileName);
            
            StreamReader reader = fileIn.OpenText();
            string[] lineIn;

            while (!reader.EndOfStream)
            {
                lineIn = reader.ReadLine().Split(',');
                //Validate values here
            }

            reader.Close();
        }

Answer 2

Use ADO with the Microsoft.Jet.OLEDB provider:

private static DataTable readCSV(string filename) {
  string path = System.IO.Path.GetDirectoryName(filename);
  string file = System.IO.Path.GetFileName(filename);

  DataTable dt = new DataTable();
  using (OleDbConnection conn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source='" + path + "';Extended Properties='text;HDR=Yes;FMT=Delimited'")) {
    OleDbDataAdapter da = new OleDbDataAdapter("SELECT * FROM " + file, conn);
    da.Fill(dt);
  }
  return dt;
}

Answer 3

How to fill all data from csv into untyped dataset?here i am not able to insert string into datetime column.it gives null if first row is datetime and next column is string .

Answer 4

It is a good way, but this does not work on 64bit machine.
I prefer StreamReader with Regex.

Answer 5

Maybe this helps too.

        void lines(string path)
        {
            string quoteText = "\"";
            string fieldDelimiter = ",";

            Regex regex = new Regex(String.Format("{0}(?<field>[^{0}]*){0}|(?<field>[^{1}]*)", quoteText, fieldDelimiter), RegexOptions.Compiled | RegexOptions.ExplicitCapture | RegexOptions.IgnorePatternWhitespace);
            int fieldGroupIndex = regex.GroupNumberFromName("field");
            using (StreamReader csv = new StreamReader(path))
            {
                string lineText;
                List<string> row = new List<string>();
                while ((lineText = csv.ReadLine()) != null)
                {
                    MatchCollection m = regex.Matches(lineText);
                    for (int i = 0; i < m.Count; i += 2)
                    {
                        row.Add(m[i].Groups[fieldGroupIndex].Value);
                        // check the values.
                    }

                    row.Clear();
                }
            }
        }