How do I setup filehelpers with a required, not empty column

c#, filehelpers

Solution

You can perform any validation you want in the `AfterReadRecord` event. If you want to continue processing the rest of the file if there is an error, you also need to set the `ErrorMode` to `SaveAndContinue`. See below for a working example.

[DelimitedRecord("|")]
public class MyClass
{
    public string Field1;
    public string Field2;
    public string Field3;
}

class Program
{
    static void Main(string[] args)
    {
        var engine = new FileHelperEngine<MyClass>();
        engine.AfterReadRecord += new FileHelpers.Events.AfterReadHandler<MyClass>(engine_AfterReadRecord);
        engine.ErrorMode = ErrorMode.SaveAndContinue;
        // import a record with an invalid Email
        MyClass[] validRecords = engine.ReadString("Hello||World");
        ErrorInfo[] errors = engine.ErrorManager.Errors;
        Assert.AreEqual(1, engine.TotalRecords); // 1 record was processed
        Assert.AreEqual(0, validRecords.Length); // 0 records were valid
        Assert.AreEqual(1, engine.ErrorManager.ErrorCount); // 1 error was found
        Assert.That(errors[0].ExceptionInfo.Message == "Field2 is invalid");
    }

    static void engine_AfterReadRecord(EngineBase engine, FileHelpers.Events.AfterReadEventArgs<MyClass> e)
    {
        if (String.IsNullOrWhiteSpace(e.Record.Field1))
            throw new Exception("Field1 is invalid");
        if (String.IsNullOrWhiteSpace(e.Record.Field2))
            throw new Exception("Field2 is invalid");
        if (String.IsNullOrWhiteSpace(e.Record.Field3))
            throw new Exception("Field3 is invalid");
    }
}

Problem

I've been looking through filehelpers documentation, but there doesn't seem anything to handle empty values in columns. I need to be able to set a 'non-empty' string attribute on all the columns. Can anyone point me in the right direction?

Original source