ActiveX properties

I currently am coding an activeX control and I need to have a property that is a string. The only string type that it appears I can use is the BSTR type. But I need it to be a LPCTSTR type. What is the code for changing the type from a BSTR to a LPCTSTR type? Iam not familiar with type casting in c++ as I usually deal with java so sorry if this is a stupid question!

Strings in COM interfaces are typically BSTRs which are WCHAR based. LPCTSTR are sometimes char based. LPCTSTR changes based on whether you are doing a unicode build or not. Therefore you cannot use LPCTSTR in a COM interface. All strings surfaced as properties in an ActiveX control must be BSTRs.

If you still want to you can convert to/from unicode strings try MSDN TN059: Using MFC MBCS/Unicode Conversion Macros. OLE2CT will convert from a BSTR to a LPCTSTR.

Quote:

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Originally posted by Mikewithersone
I currently am coding an activeX control and I need to have a property that is a string. The only string type that it appears I can use is the BSTR type. But I need it to be a LPCTSTR type. What is the code for changing the type from a BSTR to a LPCTSTR type? Iam not familiar with type casting in c++ as I usually deal with java so sorry if this is a stupid question!

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Not need to think about casting BSTR to LPCTSTR or whatever.
Let Class(good)Wizard to add a property of BSTR type (e.g. "TestProperty"), then...
add a member variable of type CString:

Code:

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class C_test_ocxCtrl : public COleControl
{
// Atributes:
protected:
  CString m_strTestProperty;
//...
};

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modify the corresponding Get/Set functions as follows:

Code:

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BSTR C_test_ocxCtrl::GetTestProperty()
{
  return m_strTestProperty.AllocSysString();
}
void C_test_ocxCtrl::SetTestProperty(LPCTSTR lpszNewValue)
{
  m_strTestProperty = lpszNewValue;
  SetModifiedFlag();
}

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When inserting the control into a project, you will see in generated wrapper class something more familiar (and no BSTRs :D

Code:

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class C_test_ocx : public CWnd
{
// ...
// Attributes
public:
  CString GetTestProperty();
  void SetTestProperty(LPCTSTR);
};

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