a few questions about Symbian C++

[schmeichel]

I have a few questions about Symbian C++ as below, could you help to answer them? thanks.

1. why we can't implement codes like this? what's its problem?

class CMyClass : CBase
{
public:
CMyClass(){
CleanupStack::PushL(this);
// do initialization that may ccause leave...
CleanupStack::Pop(); // this
}
};

2. why we need to provide an implementation of constructor of C class? Even it is an empty implementation in .CPP file, and how about implement it by inline in .H file?

3. When we should use HBuf? And, when we should use HBufC? what is their differences?

[wizard_hu_]

1. Now it is a convention only, the code snippet is expected to work. In older days it was really necessary.
2. That is a misunderstanding. There is no need for empty constructors.
3. I guess you have wanted to write RBuf. It is simply newer than HBufC, main features are that it is a modifiable descriptor and it can be passed around by value. You still need HBufC when an API mandates it, or you want to support NULL-ness for some reason.