Malformed URIs are not rewritten

[larrygoldupslide]

Steps to reproduce

• Create a Microsoft Excel workbook (from Excel UI) in which you insert a hyperlink with an invalid URI, such as file://https:\gna\gna\gna (Excel allows to insert hyperlinks with invalid URIs).

• Open that workbook with the Open XML SDK.

Observed behavior
Malformed URI exception because the URI is invalid and not rewritten.
Indeed, Open XML only rewrites the URI if Uri.TryCreate("mailto:one@") returns false, but on my computer it returns true, so other invalid URIs are not rewritten.

Expected behavior
Open XML should not throw any exception, and the invalid URIs should be rewritten into rewritten://{GUID}

Desktop:

• OS: Windows
• Office version: version 2508, build 16.0.19127.20192 64 bits
• .NET Target: .NET Framework 4.8
• DocumentFormat.OpenXml Version: 3.3.0

This is really blocking for us and we'd like to keep using Open XML :)

Thanks,
Larry

[Faibbus]

Hello,
I am running into similar issues as @larrygoldupslide, except I need malformed URI to be left as they are 😅
My main issue is that the documents I get to process can get very relaxed when it comes to external references¹, and I need to edit them without breaking/rewriting these references.

I understand that many use-cases require 100% valid output, but the flexibility Excel offers has become a common law feature.

Notes:

1. For instance, Excel will happily store this highly malformed hyperlink (\:::↑↑↓↓←→←→:::/！大家好！\(╯‵□′)╯︵┻━┻^$?|) in a Spreadsheet.