我前段时间创建了一个ATL COM服务器组件(exe)。它暴露了一些正常的COM API(派生自IDispatch),并且还触发了一些COM事件。事件机制是使用ATL IConnectionPointContainer实现的。这个COM服务器最初由一个简单的C#应用程序使用,该应用程序直接向COM服务器添加一个引用。所有的API和事件都可以在C#应用程序中正常工作。javascript的ATL COM事件
然后来到COM服务器的要求能够在网页(IE)中与JavaScript一起使用。因此,我将IProvideClassInfo2,IObjectSafety实现添加到原始COM类。但是,COM事件从未奏效。请参考下面的IDL,COM类头文件和事件触发代码。
IDL:
import "oaidl.idl";
import "ocidl.idl";
[
object,
// uuid replaced with dummy
uuid(00000000-0000-0000-0000-000000000000),
dual,
nonextensible,
helpstring("ICtrl Interface"),
pointer_default(unique)
]
interface ICtrl : IDispatch{
[id(1), helpstring("method CtrlMethod1")]
HRESULT CtrlMethod1(void);
[id(2), helpstring("method CtrlMethod2")]
HRESULT CtrlMethod2([in] ULONG Reason);
};
[
// uuid replaced with dummy
uuid(00000000-0000-0000-0000-000000000001),
version(1.0),
]
library MyControlLib
{
importlib("stdole32.tlb");
importlib("stdole2.tlb");
[
// uuid replaced with dummy
uuid(00000000-0000-0000-0000-000000000002)
]
dispinterface _ICtrlEvents
{
properties:
methods:
[id(1), helpstring("method OnCtrlEvent1")]
HRESULT OnCtrlEvent1([in] LONG ErrorCode);
[id(2), helpstring("method OnCtrlEvent2")]
HRESULT OnCtrlEvent2([in] LONG ErrorCode);
};
[
// uuid replaced with dummy
uuid(00000000-0000-0000-0000-000000000003)
]
coclass Ctrl
{
[default] interface ICtrl;
[default, source] dispinterface _ICtrlEvents;
};
};
COM类的头:
// CCtrl
class ATL_NO_VTABLE CCtrl :
public CComObjectRootEx<CComSingleThreadModel>,
public CComCoClass<CCtrl, &CLSID_Ctrl>,
public IConnectionPointContainerImpl<CCtrl>,
public CProxy_ICtrlEvents<CCtrl>,
public IDispatchImpl<ICtrl, &IID_ICtrl, &LIBID_MyControlLib, /*wMajor =*/ 1, /*wMinor =*/ 0>,
public IDispatchImpl<_ICtrlEvents, &__uuidof(_ICtrlEvents), &LIBID_MyControlLib, /* wMajor = */ 1, /* wMinor = */ 0>,
public IObjectSafetyImpl<CCtrl, INTERFACESAFE_FOR_UNTRUSTED_CALLER>,
public IProvideClassInfo2Impl<&CLSID_Ctrl, NULL, &LIBID_MyControlLib>
{
public:
DECLARE_CLASSFACTORY_SINGLETON(CCtrl)
CCtrl();
DECLARE_REGISTRY_RESOURCEID(IDR_CTRL)
BEGIN_COM_MAP(CCtrl)
COM_INTERFACE_ENTRY(ICtrl)
COM_INTERFACE_ENTRY2(IDispatch, ICtrl)
COM_INTERFACE_ENTRY2(IDispatch, _ICtrlEvents)
COM_INTERFACE_ENTRY(IConnectionPointContainer)
COM_INTERFACE_ENTRY(_ICtrlEvents)
COM_INTERFACE_ENTRY(IObjectSafety)
COM_INTERFACE_ENTRY(IProvideClassInfo)
COM_INTERFACE_ENTRY(IProvideClassInfo2)
END_COM_MAP()
BEGIN_CONNECTION_POINT_MAP(CCtrl)
CONNECTION_POINT_ENTRY(__uuidof(_ICtrlEvents))
END_CONNECTION_POINT_MAP()
DECLARE_PROTECT_FINAL_CONSTRUCT()
HRESULT FinalConstruct();
void FinalRelease();
public:
STDMETHOD(CtrlMethod1)(void);
STDMETHOD(CtrlMethod2)(ULONG Reason);
};
OBJECT_ENTRY_AUTO(__uuidof(Ctrl), CCtrl)
ATL生成的事件触发代码:
#pragma once
template<class T>
class CProxy_ICtrlEvents :
public ATL::IConnectionPointImpl<T, &__uuidof(_ICtrlEvents)>
{
public:
HRESULT OnCtrlEvent1(LONG ErrorCode)
{
HRESULT hr = S_OK;
T * pThis = static_cast<T *>(this);
int cConnections = m_vec.GetSize();
for (int iConnection = 0; iConnection < cConnections; iConnection++)
{
pThis->Lock();
CComPtr<IUnknown> punkConnection = m_vec.GetAt(iConnection);
pThis->Unlock();
IDispatch * pConnection = static_cast<IDispatch *>(punkConnection.p);
if (pConnection)
{
CComVariant avarParams[1];
avarParams[0] = ErrorCode;
avarParams[0].vt = VT_I4;
CComVariant varResult;
DISPPARAMS params = { avarParams, NULL, 1, 0 };
hr = pConnection->Invoke(1, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_METHOD, ¶ms, &varResult, NULL, NULL);
}
}
return hr;
}
HRESULT Fire_OnCtrlEvent2(LONG ErrorCode)
{
HRESULT hr = S_OK;
T * pThis = static_cast<T *>(this);
int cConnections = m_vec.GetSize();
for (int iConnection = 0; iConnection < cConnections; iConnection++)
{
pThis->Lock();
CComPtr<IUnknown> punkConnection = m_vec.GetAt(iConnection);
pThis->Unlock();
IDispatch * pConnection = static_cast<IDispatch *>(punkConnection.p);
if (pConnection)
{
CComVariant avarParams[1];
avarParams[0] = ErrorCode;
avarParams[0].vt = VT_I4;
CComVariant varResult;
DISPPARAMS params = { avarParams, NULL, 1, 0 };
hr = pConnection->Invoke(2, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_METHOD, ¶ms, &varResult, NULL, NULL);
}
}
return hr;
}
};
在JavaScript代码,是使用
创建COM对象var CtrlObj = new ActiveXObject('ProgID_of_Ctrl')
'ProgID_of_Ctrl'映射到__uuidof(Ctrl)。在IE调试器中,创建的对象是ICtrl类型的。 COM API是可见的,但COM事件不是。任何尝试使用CtrlObj.attachEvent()都会导致javascript错误。我希望CtrlObj应该是coclass(Ctrl)类型,就像C#应用程序的情况一样。 COM_MAP部分中是否有错误?任何意见和帮助表示赞赏。
-CodeFarmer
谢谢。你的解决方案有效我并不认为它是一个骗子。主界面不是提供单独的事件界面,而是为JavaScript提供了一种注册回调的方法。 – CodeFarmer 2012-02-07 05:06:20