Problem with empty $FINGERPRINTGUID

[Tilwin90]

We have a .CDX file with the following FINGERPRINTGUID section:

"$FINGERPRINTGUID
2

9"

Because no actual GUID is specified in-between, the framework attempts to read an empty string as a GUID. Here is the full stack trace:

at System.Guid.TryParseGuid(String g, GuidStyles flags, GuidResult& result) in f:\dd\ndp\clr\src\BCL\system\guid.cs:line 462
at System.Guid.Parse(String input) in f:\dd\ndp\clr\src\BCL\system\guid.cs:line 262
at IxMilia.Dxf.DxfHeader.GuidString(String s) in D:\IxMilia\Dxf\src\IxMilia.Dxf\Sections\DxfHeader.cs:line 87
at IxMilia.Dxf.DxfHeader.SetHeaderVariable(String keyName, DxfCodePair pair) in D:\IxMilia\Dxf\src\IxMilia.Dxf\Sections\Generated\DxfHeaderGenerated.cs:line 4562
at IxMilia.Dxf.Sections.DxfHeaderSection.HeaderSectionFromBuffer(DxfCodePairBufferReader buffer) in D:\IxMilia\Dxf\src\IxMilia.Dxf\Sections\DxfHeaderSection.cs:line 437
at IxMilia.Dxf.Sections.DxfSection.FromBuffer(DxfCodePairBufferReader buffer, DxfAcadVersion version) in D:\IxMilia\Dxf\src\IxMilia.Dxf\Sections\DxfSection.cs:line 71
at IxMilia.Dxf.DxfFile.LoadFromReader(IDxfCodePairReader reader) in D:\IxMilia\Dxf\src\IxMilia.Dxf\DxfFile.cs:line 257
at IxMilia.Dxf.DxfFile.Load(Stream stream) in D:\IxMilia\Dxf\src\IxMilia.Dxf\DxfFile.cs:line 188

The file can be opened just fine by regular DXF readers.
Would there be any chance this field could get ignored in this situation?

UPDATE:
I pulled the sources locally, and indeed the issue is that the static method DxfHeader.GuidString attempts convert an empty string to a Guid, resulting in an error. If performing a check for NullOrWhitespace before propagating the Guid conversion, and returning an empty Guid otherwise, it seems to work just fine.

[brettfo]

Good catch!

I slightly modified your suggestion and used Guid.TryParse() to ensure we always get something valid or Guid.Empty.

Fixed in commit 10eb796.