Parameters
- startSymbol
- A start symbol of new text region.
- stopSymbol
- A end symbol of new text region.
Return Value
A subregion of this text region.
Target Platforms: .NET 11; .NET 10; .NET 9; .NET 8; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5, 4.0, 3.5