Question

请查看以下代码

private: System::Void button3_Click(System::Object^  sender, System::EventArgs^  e)
{
    System::Speech::Recognition::SpeechRecognizer ^sr = gcnew System::Speech::Recognition::SpeechRecognizer();

    array<String ^> ^strs = gcnew array<String ^> {"Hello", "World"};

    System::Speech::Recognition::Choices ^colors = gcnew System::Speech::Recognition::Choices();
    colors->Add(strs);

    System::Speech::Recognition::GrammarBuilder ^gb = gcnew System::Speech::Recognition::GrammarBuilder();
    gb->Append(colors);

    System::Speech::Recognition::Grammar ^g = gcnew System::Speech::Recognition::Grammar(gb);
    sr->LoadGrammar(g);

    // System::IntPtr ptr = gcnew System::IntPtr(&sr_SpeechRecognized);
    sr->SpeechRecognized += gcnew System::EventHandler<System::Speech::Recognition::SpeechRecognizedEventArgs>(this,&Form1::sr_SpeechRecognized);
}

void sr_SpeechRecognized(System::Object ^sender, System::Speech::Recognition::SpeechRecognizedEventArgs^ e)
{
 }

此代码生成以下错误

1>------ Build started: Project: SpeechTest, Configuration: Debug Win32 ------
1>  SpeechTest.cpp
1>c:\users\yohan\documents\visual studio 2010\projects\speechtest\speechtest\Form1.h(144): error C3225: generic type argument for 'TEventArgs' cannot be 'System::Speech::Recognition::SpeechRecognizedEventArgs', it must be a value type or a handle to a reference type
1>c:\users\yohan\documents\visual studio 2010\projects\speechtest\speechtest\Form1.h(144): error C3352: 'void SpeechTest::Form1::sr_SpeechRecognized(System::Object ^,System::Speech::Recognition::SpeechRecognizedEventArgs ^)' : the specified function does not match the delegate type 'void (System::Object ^,System::Speech::Recognition::SpeechRecognizedEventArgs)'
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

在这里，一切正常，期望处理程序创建sr->SpeechRecognized += gcnew System::EventHandler<System::Speech::Recognition::SpeechRecognizedEventArgs>(this,&Form1::sr_SpeechRecognized);

如果你注释掉这个处理程序部分，一切都会好的。这里Form表示当前的GUI表单，即C ++ / CLI构建的默认GUI表单。所有这些代码都在这种形式中。我按照我在文章中阅读的方式创建了这个处理程序。那么有人可以帮我解决这个问题吗？

Answer 1

您错过了^。

sr->SpeechRecognized += gcnew System::EventHandler<System::Speech::Recognition::SpeechRecognizedEventArgs^>(this,&Form1::sr_SpeechRecognized);
                                                                                           // right here ^

仔细查看收到的错误消息，删除命名空间，并使用换行符使事情排成一行。

     error C3352: 'void SpeechTest::Form1::sr_SpeechRecognized(Object^,SpeechRecognizedEventArgs^)' : 
the specified function does not match the delegate type 'void (Object^,SpeechRecognizedEventArgs)'
                                                                                                ^

您正在尝试创建一个带有SpeechRecognizedEventArgs的方法的委托，但您要为其指定一个带SpeechRecognizedEventArgs^的方法的名称。

如何在C ++ / CLI中创建C＃事件处理程序？

1 个答案: