Generate txt file according to the predefined layout in c#

Question

I need to export data from a class according to a specific layout consisting of size and position.

For easy maintenance, I need simple layout change.

Follow down my class:

    public class NovosCotistasDTO
    {
        public string Agencia { get; set; }
        public string Conta { get; set; }
        public DateTime DataInclusao { get; set; }
        public string Tipo { get; set; }
        public string IdUsuario { get; set; }
        public string CNPJ { get; set; }
    }  

Below follows Layout that must be exported:

Campo           |Tamanho    |Posição Inicial    |Posição Final
--------------------------------------------------------------
Agencia         |5          |1                  |5
Conta           |13         |6                  |19
DataInclusao    |10         |20                 |30
Tipo            |1          |31                 |32
IdUsuario       |7          |33                 |40
CNPJ            |14         |41                 |55

Answer 1

The library Filehelpers does exactly what you need.

With it you can set file layouts by size and position.

In your specific case, after importing the Filehelpers in your project, you would implement as follows:

Class Defining the Layout

Reply Edition: it is necessary to use simple fields instead of properties (get / set).

using FileHelpers;

[FixedLengthRecord(FixedMode.ExactLength)]
public class NovosCotistasDTO
{
    [FieldFixedLength(5)]
    public string agencia;

    [FieldFixedLength(13)]
    public string conta;

    [FieldFixedLength(10)]
    [FieldConverter(ConverterKind.Date, "ddMMyyyy")] // Outros formatos de data são possíveis. Ex: "DD/MM/AAAA", "ddMMyyyyHHmmss", etc.
    public DateTime dataInclusao;

    [FieldFixedLength(1)]
    public string tipo;

    [FieldFixedLength(7)]
    public string idUsuario;

    [FieldFixedLength(14)]
    public string cnpj;
} 

How to Save Records to TXT File

Writing a log file using Filehelpers is quite simple. You take a list of the objects you want to save to file and pass to Filehelpers as follows:

public void EscrevaArquivo(string nomeDoArquivo, List<object> registros)
{
    FileHelperEngine engine = new FileHelperEngine(typeof(NovosCotistasDTO));

    engine.WriteFile(nomeDoArquivo, registros);
}

How to Read Saved Records in File

To get back the records you saved using this layout, just do it as follows:

public List<NovosCotistasDTO> LeiaArquivo(string nomeDoArquivo)
{
    var engine = new FileHelperEngine(typeof(NovosCotistasDTO));

    var linhasDoArquivo = engine.ReadFile(nomeDoArquivo);

    var listaDeRegistros = new List<NovosCotistasDTO>();

    foreach (var linha in linhasDoArquivo)
    {
        lista.Add((NovosCotistasDTO)linha);
    }

    return listaDeRegistros;
}

Answer 2

There are several ways to solve it. One of my favorites is to make a override of ToString():

public class NovosCotistasDTO
{
    public string Agencia { get; set; }
    public string Conta { get; set; }
    public DateTime DataInclusao { get; set; }
    public string Tipo { get; set; }
    public string IdUsuario { get; set; }
    public string CNPJ { get; set; }

    public override String ToString() 
    {
        return Agencia.Replace("-", "") + 
            Conta.Replace("-", "").Replace(".", "") +
            DataInclusao.ToString("dd/MM/yyyy") +
            Tipo.Substring(0, 30) +
            IdUsuario.Substring(0, 7) +
            CNPJ.Replace("-", "").Replace(".", "").Replace("/", "")
    }
}

Use:

var cotistaDto = new NovosCotistasDTO 
{
    Agencia = "1234",
    Conta = "12345-6",
    DataInclusao = DateTime.Now,
    Tipo = "Tipo",
    IdUsuario = "Usuario",
    CNPJ = "12.345.678/0001-99"
};

String layout = cotistaDto.ToString();

Note that this solution is quite simple, and the character control is entirely manual.

Using String.Format it is possible to do something even more sophisticated, but it is necessary to better understand how are your data conditions:

• What happens when a die is bigger than the mask;
• How data is assigned in your DTO;
• Other validation conditions.