如何调试COM DLL
在“解决方案资源管理器”中，右击组件项目并单击快捷菜单上的“属性”。<项目名称>“属性页”对话框中，打开“配置属性”文件夹并选定“调试”类别。在“命令”框中，键入如下内容：dllhost.exe 在“命令参数”框中，键入参数 /ProcessID，继之以应用程序 ID（library XXX）上的GUID。例如：/ProcessID:{3D14228C-FBE1-11D0-995D-0C04FD919C1} 单击“确定”。这样设置后就可以调试了。 如果客户端是C#，再设置客户端项目调试选项中可以调试非托管代码。
总是出现"char * __stdcall _com_util::ConvertBSTRToString的错误
只要在某个文件中添加对comdef.h的包含就可以，这个头文件会链接库，仅包含comutil.h并不会链接相应的库。
7-27日：
C# .net framework4.0 传递SAFEARRAY的问题。
I am able to call a COM interface method using SAFEARRAY(BSTR) as input. If I define instead a simple (containing only some BSTR-s fields) STRUCT to pass into the COM I get "[System.ArgumentException] = {"The parameter is incorrect. (Exception from HRESULT: 0x80070057 (E_INVALIDARG))"
The call to my COM server is not made because as it seems the arguments from client does not match the expected arguments on server: E_INVALIDARG
Here is my declaration in IDL:
typedef enum UserEntityType
{
User,
Group,
IPAddress
} UserEntityType;
[
uuid(4786F77E-BA5F-4806-B224-12AA8601A5B1)
]
typedef struct UserEntity
{
UserEntityType EntityType;
BSTR Value;
} UserEntity;
[id(9)] HRESULT SetUsers([in] SAFEARRAY(UserEntity) input);
The exception is thrown at run-time when a C# 4 client calls SetUsers().
solution:The problem was in the C# client that was using the exe COM server where
SetUsers([in] SAFEARRAY(UserEntity) input)
was defined. In order to fix this (at least for .NET 4.0) one has to change the following property of the imported COM server: Embed Interop Types = False