ATL---Collection & Enumerater（3）_atl 导出 collection-优快云博客

本文链接：https://blog.youkuaiyun.com/massice/article/details/5895462

本文介绍如何使用ATL模板CComEnumOnSTL和ICollectionOnSTLImpl来实现COM接口INumbers3，该接口提供了数值集合的操作，包括获取元素数量、按索引获取元素值及提供枚举器。

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练习三：使用CComEnumOnSTL实现，使用的IEnumVARIANT枚举接口；使用ICollectionOnSTLImpl实现集合。

这种方法基本全由ATL模板提供实现，组件基本上不用写什么代码。

1.IDL文件

import "oaidl.idl"; import "ocidl.idl"; [ object, uuid(2D44DAAD-98D9-4786-A91C-848D6DBEC1D1), dual, nonextensible, helpstring("INumbers3 接口"), pointer_default(unique) ] interface INumbers3 : IDispatch{ [propget, id(1), helpstring("属性 Count")] HRESULT Count([out, retval] LONG* pVal); [propget, id(DISPID_VALUE), helpstring("属性 Item")] HRESULT Item([in] LONG n, [out, retval] LONG* pVal); [propget, id(DISPID_NEWENUM), helpstring("属性 _NewEnum")] HRESULT _NewEnum([out, retval] IUnknown** pVal); }; [ uuid(93FBE6A0-AEA8-40A4-B1E0-C085E4C7F9AD), version(1.0), helpstring("MyNumbers3 1.0 类型库") ] library MyNumbers3Lib { importlib("stdole2.tlb"); [ uuid(B305004A-27F7-491C-94F9-47DF5CF3615F), helpstring("Numbers3 Class") ] coclass Numbers3 { [default] interface INumbers3; }; };

2.Numbers3.h

class _CopyVariantFromLong { public: static HRESULT copy(VARIANT* p1, const long* p2) { p1->vt = VT_I4; p1->lVal = *p2; return S_OK; } static void init(VARIANT *p) {VariantInit(p);} static void destroy(VARIANT *p) {VariantClear(p);} }; typedef CComEnumOnSTL< IEnumVARIANT,&IID_IEnumVARIANT,VARIANT,_CopyVariantFromLong,std::vector<long> > MyEnumOnSTL; typedef ICollectionOnSTLImpl<INumbers3,std::vector<long>,long,_Copy<long>,MyEnumOnSTL> MyCollectionOnSTL; // CNumbers3 class ATL_NO_VTABLE CNumbers3 : public CComObjectRootEx<CComSingleThreadModel>, public CComCoClass<CNumbers3, &CLSID_Numbers3>, public IDispatchImpl<MyCollectionOnSTL, &IID_INumbers3, &LIBID_MyNumbers3Lib, /*wMajor =*/ 1, /*wMinor =*/ 0> //public IDispatchImpl<INumbers3, &IID_INumbers3, &LIBID_MyNumbers3Lib, /*wMajor =*/ 1, /*wMinor =*/ 0> { public: CNumbers3() { m_coll.push_back(101); m_coll.push_back(202); m_coll.push_back(303); m_coll.push_back(404); } DECLARE_REGISTRY_RESOURCEID(IDR_NUMBERS3) BEGIN_COM_MAP(CNumbers3) COM_INTERFACE_ENTRY(INumbers3) COM_INTERFACE_ENTRY(IDispatch) END_COM_MAP() DECLARE_PROTECT_FINAL_CONSTRUCT() HRESULT FinalConstruct() { return S_OK; } void FinalRelease() { } public: }; OBJECT_ENTRY_AUTO(__uuidof(Numbers3), CNumbers3)

3.Number3.cpp ------ 啥也不用俺写了，ATL全搞定

4.测试Client

// TestNumbers3.cpp : 定义控制台应用程序的入口点。 // #include <iostream> #include <atlbase.h> #include <atlcomcli.h> #include <atlcom.h> #include "../MyNumbers3/MyNumbers3.h" #include "../MyNumbers3/MyNumbers3_i.c" using namespace std; int main(int argc, _TCHAR* argv[]) { CoInitialize(NULL); try { CComPtr<INumbers3> pNum = NULL; HRESULT hr; hr = CoCreateInstance(CLSID_Numbers3,NULL,CLSCTX_INPROC,IID_INumbers3,(void**)&pNum); if (FAILED(hr)) { cout << "CoCrateInstance error." << endl; CoUninitialize(); return -1; } long lSize = 0; pNum->get_Count(&lSize); cout << "Size: " << lSize << endl; CComPtr<IEnumVARIANT> pEnum = NULL; CComPtr<IUnknown> pUnknown = NULL; pNum->get__NewEnum(&pUnknown); pUnknown->QueryInterface(IID_IEnumVARIANT,(void**)&pEnum); for (int i=1;i<=lSize;i++) { VARIANT varTemp[1]; ULONG lFetched = 0; hr = pEnum->Next(1,&varTemp[0],&lFetched); if (SUCCEEDED(hr)) { CComVariant comvar; comvar.Attach(&varTemp[0]); wcout << "Number " << i << " is " << comvar.lVal << endl; } } } catch (...) { cout << "an expection occur......" << endl; } CoUninitialize(); system("pause"); return 0; }