如何让 FileHelpers 忽略定义列之后的列？ （即忽略末尾的列）

Question

假设我有以下 FileHelpers 记录定义：

[DelimitedRecord(",")]
[IgnoreEmptyLines]
public class TestRecord
{
    [FieldCaption("A")]
    [FieldQuoted(QuoteMode.OptionalForBoth)]
    public string A;

    [FieldCaption("B")]
    [FieldQuoted(QuoteMode.OptionalForBoth)]
    public string B;

    [FieldCaption("C")]
    [FieldQuoted(QuoteMode.OptionalForBoth)]
    public string C;
}

我只对 A、B、C 列感兴趣。它们后面的任何列都可以忽略。因此，例如，我希望能够像这样处理数据：

A,B,C,D,E
TestA1,TestB1,TestC1,TestD1,TestE1
TestA2,TestB1,TestC1,TestD1,TestE1

或：

A,B,C,D
TestA1,TestB1,TestC1,TestD1
TestA2,TestB1,TestC1,TestD1

或：

A,B,C
TestA1,TestB1,TestC1
TestA2,TestB1,TestC1

Answer 1

只需在 class 的末尾添加一个额外的 string[] 字段并将其标记为 [FieldOptional]。

[DelimitedRecord(",")]
[IgnoreEmptyLines]
public class TestRecord
{
    [FieldCaption("A")]
    [FieldQuoted(QuoteMode.OptionalForBoth)]
    public string A;

    [FieldCaption("B")]
    [FieldQuoted(QuoteMode.OptionalForBoth)]
    public string B;

    [FieldCaption("C")]
    [FieldQuoted(QuoteMode.OptionalForBoth)]
    public string C;

    [FieldOptional]
    public string[] EverythingElse;
}

class Program
{
    static void Main(string[] args)
    {
        var engine = new FileHelperEngine<TestRecord>();
        var records = engine.ReadString("TestA1,TestB1,TestC1,TestD1,TestE1");
        
        Debug.Assert(records.Count() == 1);
        Debug.Assert(records[0].A == "TestA1");
        Debug.Assert(records[0].B == "TestB1");
        Debug.Assert(records[0].C == "TestC1");

        Console.WriteLine("All OK");
        Console.ReadLine();
    }
}