DataTableRow's CopyTo throws

[zdenek-jelinek]

DataTableRow.CopyTo throws the following exception:

Reqnroll.ReqnrollException
The table rows must contain the same number of items as the header count of the table. The structure cannot be modified.

As someone who occasionally processes tables row by row (e.g. to dynamically validate xlsx export data against gherkin spec), it's very helpful for me to use LINQ methods such as ToList. Unfortunately, these tend to call ICollection::CopyTo internally if they manage to downcast the source collection.

This can be reproduced with code such as

var table = new DataTable("Field", "Value");
table.AddRow("Dummy Field", "Dummy Value");
var entries = table.Rows[0].ToList();

It can be worked around by introducing another iterator such as using .Select(x => x).ToList() to avoid the ICollection downcast.

Is there a reason for throwing here? Both KeyValuePair<,> and string are immutable so I think it should be safe for the table's structure to copy the data outside. Is this perhaps an omission? Would you be open to a PR to change this? Or could we possibly change the exception message to better describe the error, if it is intended?

[304NotModified]

Sounds like a bug to me!