Add .Net 9.0 support

Author: Mizux

CMakeLists.txt

@@ -141,14 +141,19 @@ message(STATUS ".Net: Use .Net 7.0 support: ${USE_DOTNET_7}")
 option(USE_DOTNET_8 "Use .Net 8.0 LTS support" OFF) # EOL: 2026-11-10
 message(STATUS ".Net: Use .Net 8.0 support: ${USE_DOTNET_8}")
 
+option(USE_DOTNET_9 "Use .Net 9.0 support" OFF) # EOL: 2026-05-14
+message(STATUS ".Net: Use .Net 9.0 support: ${USE_DOTNET_9}")
+
 include(dotnet)
 
 add_subdirectory(tests)
 
 option(BUILD_EXAMPLES "Build examples" ON)
 message(STATUS "Build examples: ${BUILD_EXAMPLES}")
 
-if(USE_DOTNET_8)
+if(USE_DOTNET_9)
+  set(EXAMPLE_DEFAULT_TFM "net9.0")
+elseif(USE_DOTNET_8)
   set(EXAMPLE_DEFAULT_TFM "net8.0")
 elseif(USE_DOTNET_7)
   set(EXAMPLE_DEFAULT_TFM "net7.0")

cmake/dotnet.cmake

@@ -85,6 +85,9 @@ endif()
 if(USE_DOTNET_8)
   list(APPEND TFM "net8.0")
 endif()
+if(USE_DOTNET_9)
+  list(APPEND TFM "net9.0")
+endif()
 
 list(LENGTH TFM TFM_LENGTH)
 if(TFM_LENGTH EQUAL "0")
@@ -227,6 +230,9 @@ function(add_dotnet_test FILE_NAME)
   if(USE_DOTNET_8)
     add_dotnet_tfm_test(${FILE_NAME} net8.0)
   endif()
+  if(USE_DOTNET_9)
+    add_dotnet_tfm_test(${FILE_NAME} net9.0)
+  endif()
   message(STATUS "Configuring test ${FILE_NAME} ...DONE")
 endfunction()