Can I add validate feature in Set parameter, and throw exception, and show usage?

[Wenduan-Mou]

Can I add validate feature in Set parameter, and throw exception, and show usage?
is there exception handling in command line parameter parsing?

[Option(
'f', "filename",
HelpDesk = "Specifies the input file")]
public string Name
{
get { return mName; }
set
{
Regex regex = new Regex("^[0-9a-z]+.txt$");

     if (regex.Match(value).Success )
        throw new InvalidOptionValueException(
            "The name must be txt file", false);
     mName = value;
  }

}
Private string mName;

[e673]

No, there is no such exception handling.
Try this code:

try
{
    var result = Parser.Default.ParseArguments(...);
}
catch (InvalidOperationException e)
{
    if (e.InnerException is TargetInvocationException targetInvocationException)
    {
        var innerException = targetInvocationException.InnerException;
        Console.Error.WriteLine(innerException.Message);
    }
}

P.S. I will try to implement this feature now.

[e673]

I've implementing it here:
https://github.com/e673/commandline/tree/issue283
I will make a pull request after adding tests.

[mmajcica]

I just tried this and it works as expected! Thanks