FileHelper can't handle ReSharper sorting variables in its classes

Question

I have code doing this:

var engine = new FileHelperEngine<SampleType>();
var records = engine.ReadString("asdf|fdsa");

var showString = records[0].Field1 + records[0].Field2;

The SampleType class looks like this:

[DelimitedRecord("|")]
public class SampleType
{
    public string Field2;
    public string Field1;
}

The resultset is as follows:

records[0].Field1 has the value fdsa

records[0].Field2 has the value asdf

If I run a ReSharper cleanup it will sort the variables alphabetically. And the SampleType class will look like this:

[DelimitedRecord("|")]
public class SampleType
{
    public string Field1;
    public string Field2;
}

But now the logic of my program has changed.

records[0].Field1 has the value asdf

records[0].Field2 has the value fdsa

Is there a way to tell the classes that the order of the defined variables is irrelevant? That the defining order of variables is suddenly relevant, contrary to any other class I have ever seen, I find very disturbing and strange.

Answer 1

I'm not completely sure, but I think you want a way to make FileHelpers use an explicitly-specified ordering for the fields, rather than the implicit 'the order they are defined in in the source'.

If I'm right, you want the FieldOrder attribute from the FileHelpers library:

Force field order with [FieldOrder] attribute:

//-> You first declare a Record Mapping class:
Input.txt

10248|VINET|04071996|32.38
10249|TOMSP|05071996|11.61
10250|HANAS|08071996|65.83
10251|VICTE|08071996|41.34


RecordClass.cs

[DelimitedRecord("|")]
public class Orders
{
    [FieldOrder(20)]
    public string CustomerID;

    [FieldConverter(ConverterKind.Date, "ddMMyyyy")]
    [FieldOrder(30)]
    public DateTime OrderDate;

    [FieldConverter(ConverterKind.Decimal, ".")] // The decimal separator is "."
    [FieldOrder(40)]
    public decimal Freight;

    [FieldOrder(10)]
    public int OrderID;
}

As to your comment

However I am quite surprised of how OK this way of solving a problem in such a library seems to you. And for the record, this is not logical, and to be able to understand it, you'll have to "overthink" :p It's not a part of the languages design

You're right in that the default operation mode of FileHelper here (to use the source-ordering of fields as their in-record ordering) isn't 'native' C#, and indeed isn't a particularly 'C#-ish' way of doing things; BUT that's OK if it's how the authors and users of FileHelpers want it. It does have the flavour of a more dynamic-language style, but then that's a bit how C# is headed anyway...