的Visual C++枚舉（CloseReason）

Question

當我寫：

private: System::Void queue_FormClosing(
    System::Object^ sender, 
    System::Windows::Forms::FormClosingEventArgs^ e) { 
    if(e->CloseReason!=CloseReason::FormOwnerClosing) e->Cancel=true; 
} 

我得到這個錯誤：

###\queue.h(153) : error C2039: 'FormOwnerClosing' : is not a member of 'System::Windows::Forms::Form::CloseReason' 1>###\queue.h(24) : see declaration of 'System::Windows::Forms::Form::CloseReason' 1>###\queue.h(153) : error C2065: 'FormOwnerClosing' : undeclared identifier

我不明白這是爲什麼。任何人都可以幫忙嗎？

Answer 1

由於某些原因，您需要完全限定枚舉爲System :: Windows :: Forms :: CloseReason :: FormOwnerClosing。

不會編譯：

private: System::Void Form1_FormClosing(System::Object^ sender, 
       System::Windows::Forms::FormClosingEventArgs^ e) { 
    if (e->CloseReason == CloseReason::FormOwnerClosing) { 
    e->Cancel = true; 
    } 
} 

是否編譯：

private: System::Void Form1_FormClosing(System::Object^ sender, 
       System::Windows::Forms::FormClosingEventArgs^ e) { 
    if (e->CloseReason == System::Windows::Forms::CloseReason::FormOwnerClosing) { 
    e->Cancel = true; 
    } 
} 

不知道爲什麼你需要完全限定它，但它允許它來編譯。