Fixed CsvOutputFormatter bug where a return type was not IEnumerable<T> but is … #204
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Fixed bug where a return type which implements IEnumerable but is not itself generic (or perhaps not [generic]) would fail when UseSingleLineHeaderInCsv was true.
This happened to me in .NET Core 3.1 using the pretty simple controller method:
[HttpGet]
[Produces("text/csv")]
public IEnumerable Get(string id)
Perhaps this was caused by how "yield return" is handled by the compiler. I would have looked into that further, except that it was a flaw and fixing the flaw is more important.