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MultiRecordEngine does not expose Options for all record types
The MultiRecordEngine
class exposes an Options
property that lets developers dynamically access and change field properties, but that Options
object only contains information about the first record type passed to the MultiRecordEngine
's constructor. It is not possible to access the field options of the remaining types.
I have a record type that contains a variable length array. Unfortunately, this array is not the final field in the record. This record type also comes from a third-party, so I have no power to change it. A simplified version of this type is shown below.
[DelimitedRecord("~")]
internal class DetailReject {
public string RecordType { get; set; }
public int NumberOfErrorCodes { get; set; }
public string[] ErrorCodes { get; set; }
public string ReferenceNumber { get; set; }
}
If I try to use the [FieldArrayLength]
attribute on the ErrorCodes
property, it demands a single fixed value. The actual count of ErrorCodes
is variable and included in the record itself as NumberOfErrorCodes
.
I would like to dynamically change the ErrorCodes
field options, similar to the Dynamic Engine Options example in the docs. However, I cannot access the options for this field because I'm using the MultiRecordEngine
and the record type is not the first type passed to that constructor.
My workaround has been to add a dummy value to the [FieldArrayLength]
attribute, and then to use reflection to access the internal and private fields that contain the field options for ErrorCodes
. This logic is added to the BeforeRead
method of the record type, which sets both ArrayMinLength
and ArrayMaxLength
to the actual count. FileHelpers then parses the record without issue.
Alternatively, a new API that allowed variable length arrays, with the expected length within the same record type, would be appreciated. Even in my workaround, I can't use the NumberOfErrorCodes
property; I have to manually compute the number of error codes using only the RecordLine
string. If possible, an attribute such as the following would meet my needs.
public int NumberOfErrorCodes { get; set; }
[FieldArrayLength(nameof(NumberOfErrorCodes))]
public string[] ErrorCodes { get; set; }
Hi @bcallaghan-et , If you used array in the import model, it can parse array of any length coming from file.
Here is file content I tested
10248|VINET|5|04071996|01081996|16071996|3|32.38|["order1"|"order2"|"order3"]
10249|TOMSP|6|05071996|16081996|10071996|1|11.61|["order1"|"order2"]
ALFKI;Alfreds Futterkiste;Maria Anders;Sales Representative;Obere Str. 57;Berlin;Germany
ANATR;Ana Trujillo Emparedados y helados;Ana Trujillo;Owner;Avda. de la Constitución 2222;México D.F.;Mexico
10250|HANAR|4|08071996|05081996|12071996|2|65.83|["order1"]
10111314012345
11101314123456
10251|VICTE|3|08071996|05081996|15071996|1|41.34|["order4"]
11121314901234
10101314234567
ANTON;Antonio Moreno Taquería;Antonio Moreno;Owner;Mataderos 2312;México D.F.;Mexico
BERGS;Berglunds snabbköp;Christina Berglund;Order Administrator;Berguvsvägen 8;Luleå;Sweden
I used below import model
[DelimitedRecord(",")] public class Order { public int OrderID;
public string CustomerID;
[FieldConverter(ConverterKind.Date, "ddMMyyyy")]
public DateTime OrderDate;
[FieldConverter(ConverterKind.Decimal, ".")] // The decimal separator is .
public decimal Freight;
**public string[] OrderItems;**
}
Code used to read file var engine = new MultiRecordEngine(typeof(Orders), typeof(Customer), typeof(SampleType));
CustomRecordTypeSelector recordTypeSelector = new CustomRecordTypeSelector();
engine.RecordSelector = new RecordTypeSelector(recordTypeSelector.CustomSelector);
var res = engine.ReadFile("..\\Files\\input.txt");
foreach (var rec in res)
Console.WriteLine(rec.ToString());