Windows环境：具有Dart 2.1.0-dev.2.0和Visual Studio 2008的Windows 7 x64。
当我尝试从example编译dll文件时，会发生错误。我使用instruction并尝试满足所有条件。
如何解决？如何编译dll文件？
视频：https://drive.google.com/file/d/1FjSIo-2U4F1JlYjvFQGxCu-jIcvGS4Xw/view
Git：https://github.com/StekolschikovV/sample_extension/tree/master/sample_extension
错误：
Warning 1 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 795 sample_extension
Error 2 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 795 sample_extension
Warning 3 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 803 sample_extension
Error 4 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 803 sample_extension
Warning 5 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 814 sample_extension
Error 6 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 814 sample_extension
Warning 7 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 1021 sample_extension
Error 8 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 1021 sample_extension
Warning 9 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 1043 sample_extension
Error 10 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 1043 sample_extension
Warning 11 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 1092 sample_extension
Error 12 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 1092 sample_extension
Warning 13 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 1253 sample_extension
Error 14 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 1253 sample_extension
Warning 15 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 1263 sample_extension
Error 16 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 1263 sample_extension
Warning 17 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 1304 sample_extension
Error 18 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 1304 sample_extension
Warning 19 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 2296 sample_extension
Error 20 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 2296 sample_extension
Warning 21 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 2310 sample_extension
Error 22 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 2310 sample_extension
Warning 23 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 2351 sample_extension
Error 24 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 2351 sample_extension
Warning 25 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 2367 sample_extension
Error 26 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 2367 sample_extension
Warning 27 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 2392 sample_extension
Error 28 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 2392 sample_extension
Warning 29 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 2418 sample_extension
Error 30 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 2418 sample_extension
Warning 31 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 2441 sample_extension
Error 32 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 2441 sample_extension
Warning 33 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 2967 sample_extension
Error 34 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 2967 sample_extension
Warning 35 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3001 sample_extension
Error 36 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3001 sample_extension
Warning 37 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3112 sample_extension
Error 38 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3112 sample_extension
Warning 39 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3129 sample_extension
Error 40 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3129 sample_extension
Warning 41 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3144 sample_extension
Error 42 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3144 sample_extension
Warning 43 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3185 sample_extension
Error 44 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3185 sample_extension
Warning 45 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3200 sample_extension
Error 46 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3200 sample_extension
Warning 47 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3218 sample_extension
Error 48 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3218 sample_extension
Warning 49 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3351 sample_extension
Error 50 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3351 sample_extension
Warning 51 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3362 sample_extension
Error 52 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3362 sample_extension
Warning 53 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3410 sample_extension
Error 54 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3410 sample_extension
Warning 55 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3418 sample_extension
Error 56 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3418 sample_extension
Warning 57 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3428 sample_extension
Error 58 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3428 sample_extension
Warning 59 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3447 sample_extension
Error 60 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3447 sample_extension
Warning 61 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3471 sample_extension
Error 62 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3471 sample_extension
Warning 63 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3480 sample_extension
Error 64 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3480 sample_extension
Warning 65 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_api.h 3500 sample_extension
Error 66 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_api.h 3500 sample_extension
Warning 67 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_native_api.h 170 sample_extension
Error 68 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_native_api.h 170 sample_extension
Warning 69 warning C4091: '__declspec(dllexport)' : ignored on left of 'int' when no variable is declared c:\program files\dart\dart-sdk\include\dart_native_api.h 176 sample_extension
Error 70 error C2143: syntax error : missing ';' before '[' c:\program files\dart\dart-sdk\include\dart_native_api.h 176 sample_extension