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csvreflectionfilehelperscsvhelper

CSV Parser, how to auto discover col names & types

I am loading CVS files for data import. The files come from various sources so the header names and location are often changing. I searched and found helpful libs like CsvHelper & FileHelpers

Question: either using FileHelper.net or CsvHelper, how do we extract both the Header names & the Column datatype? so that I can create a drop for each col, to map between .NET type <==> to a SQL type

Solution

  • Just read in the first line of the file with, say, 

    string headers = File.ReadLines("MyFile.txt").First();

    And then use a class builder to build whatever CSV spec you need.

    DelimitedClassBuilder cb = new DelimitedClassBuilder("MyProduct", delimiter: ",");

cb.AddField("Name", typeof(string));
cb.LastField.TrimMode = TrimMode.Both;

cb.AddField("Description", typeof(string));
cb.LastField.FieldQuoted = true;
cb.LastField.QuoteChar = '"';
cb.LastField.QuoteMode = QuoteMode.OptionalForBoth;

// etc... e.g., add a date field
cb.AddField("SomeDate", typeof(DateTime));

engine = new FileHelperEngine(cb.CreateRecordClass());

DataTable dt = engine.ReadFileAsDT("test.txt");