How to read flat file schema using Reflection in C #

It's hard to know where to start this question because it looks like reflection is unlikely to be helpful, and yet you indicated that it should appear in the solution! :)

As a result, this answer is mostly a guess and is likely to evolve as you uncover more information. It is perfectly; you cannot get the answer (42) until you know what the question is.

There is no single definition of what a flat file is. You probably want a function that parses the "records" in the file. The usual approach is to open the file in a hex editor and infer the format from a few sample entries. Look for clues about the shape of the repeating pattern. Seems like each "record" consists of several "fields"? Do they come out in a specific order each time, or is each field prefixed with a name or number to indicate what it means? It looks like plain text i.e. Can you open it in Notepad without losing important information?

Declare a class to represent the record:

public class FlatFileRecord
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    // etc.
}

      

        
        
        
      

    

Then write a function that reads from the stream and outputs the entries:

public static IEnumerable<FlatFileRecord> ParseFlatFile(StreamReader stream)
{
    // etc.

      

        
        
        
      

    

It would make sense to use a StreamReader if the file is "plain text" (that is, it has carriage return / line feed characters that are used in some significant way to delimit records or fields).

Suppose each record is a line of plain text (in other words, each record is separated by a special line ending sequence). Within this line, there are several fields that are somehow delimited by other special characters. Your parser can be structured like a loop:

string line;
while ((line = r.ReadLine()) != null)
    yield return new FlatFileRecord(line);

      

        
        
        
      

    

This breaks the problem down into two levels. The outer layer traverses the lines one at a time, each of which makes one record. Then there is the inner layer, which I imagined when creating the FlatFileRecord constructor. Pass in a string and it is filled with field values ​​that it knows how to extract from that string. So now you need to write the FlatFileRecord constructor.