[英]Can't port C# code to managed C++ implementing IDataErrorInfo
這部分。 注釋代碼是cs。 在編譯時捕獲錯誤:
Error 78
error C3766: 'Sample::NoteInfo' must provide an implementation for the interface method 'System::String ^System::ComponentModel::IDataErrorInfo::default::get(System::String ^)'
d:\dev\docstreet\sample\pointInfoStoreClass.h 100
什么不正確? 為什么VS編譯器認為這沒有實現?
//Returns an error description set for the item's property
//String^ IDataErrorInfo.this[String^ columnName] {
// get {
// return GetColumnError(columnName);
// }
//}
public: property String^ IDataErrorInfo[String^] {
virtual String^ get(String^ index) override {
return GetColumnError(index);
}
}
完整代碼:
public ref class NoteInfo : IDataErrorInfo {
int fDay;
int fMonth;
int fYear;
int fNoteID;
//References the item's owner
ProjectNotes^ owner;
//Stores error descriptions for the Day, Month, Year and NoteID properties
Hashtable^ propertyErrors;
//Stores an error description for the item
String^ fNoteError;
public: NoteInfo(int noteID, int day, int month, int year) {
fNoteID = noteID;
fDay = day;
fMonth = month;
fYear = year;
//Set errors to empty strings
propertyErrors = gcnew Hashtable();
propertyErrors->Add('Day', '');
propertyErrors->Add('Month', '');
propertyErrors->Add('Year', '');
propertyErrors->Add('NoteID', '');
fNoteError = '';
Owner = nullptr;
}
public: property int NoteID {
int get() { return fNoteID; }
void set(int value) {
if(fNoteID == value) return;
fNoteID = value;
}
}
public: void ClearErrors() {
SetColumnError('Day', '');
SetColumnError('Month', '');
SetColumnError('Year', '');
fNoteError = '';
}
//Sets an error for an item's property
public: void SetColumnError(String^ elem, String^ error) {
if(propertyErrors->ContainsKey(elem)) {
if((String^)propertyErrors[elem] == error) return;
propertyErrors[elem] = error;
}
}
//Gets an error for an item's property
public: String^ GetColumnError(String^ elem) {
if(propertyErrors->ContainsKey(elem))
return (String^)propertyErrors[elem];
else
return '';
}
//The owner collection
internal: property ProjectNotes^ Owner {
ProjectNotes^ get() { return owner; }
void set(ProjectNotes^ value) { owner = value; }
}
#pragma region IDataErrorInfo Members
//Returns an error description set for the item's property
//String^ IDataErrorInfo.this[String^ columnName] {
// get {
// return GetColumnError(columnName);
// }
//}
public: property String^ IDataErrorInfo[String^] {
virtual String^ get(String^ index) override {
return GetColumnError(index);
}
}
//Returns an error description set for the current item
public: property String^ Error {
virtual String^ get() { return fNoteError; }
}
#pragma endregion
};
C# 和 C++/CLI 語言都需要一個類的索引器的特殊名稱,以允許編譯器將其識別為索引器。 C# 使用this ,C++/CLI 使用default關鍵字。 MSDN 庫將其稱為“項目”以增加混淆,這在某種程度上是不可避免的,因為名稱取決於語言。 所以它必須看起來像這樣:
public: property String^ default[String^] {
virtual String^ get(String^ index) {
// etc...
}
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.