Hi! Support for multiline strings was added in VB.NET 14 (released in 2015).

I came across broken highlighting for one of my code files and saw that LexVB.cxx does not support multiline strings. So, naturally I forked and patched.

I have gated the support for the feature behind the property lexer.vb.strings.multiline for the sake of downstream compatibility, though I am not sure if something else is preferred.

Preview of the change:

Attached is a patch file containing the changes, including a test case for the feature.
vbnet14_multiline_str.patch

Thank you.