The ITDkValue custom interface

The ITDkValue custom interface is provided for the users of the HCL OneDB™ C++ Interface. ITDkValue is a C++ class factory; when a query of the database server results in an ActiveX value object, an ITDkValue object is returned to you.

The ITDkValue object is an Object Interface for C++ ITValue object; thus, the ITDkValue interface provides the same methods as the ITValue interface. You can use this interface, or you can use the QueryInterface() routine to get the IDispatch interface of the object to access its custom methods.

In addition, a global function is provided, which returns an ITValue object. It has the following syntax, where Opaque is the current object and ITMVDesc is an Object Interface for C++ descriptor structure:
ITValue * OpaqueMakeValue(ITMVDesc *description)

For information about using the Object Interface for C++, see the HCL OneDB Object Interface for C++ Programmer's Guide.

The ITDkValue interface provides the following methods.
Table 1. ITDkValue interface methods
Method Description
ITBool CompatibleType(ITValue *object) Returns TRUE if the specified object is of the same type as the current object.
ITBool Equal(ITValue *object) Returns TRUE if the specified object is equal to the current object.
ITBool FromPrintable(const ITString &printable) Sets the value of the current object by using a string equivalent to the one returned by the input function of the object.
ITBool IsNull() Returns TRUE if the current object has a null value.
ITBool IsUpdated() Returns TRUE if the current object has been updated since it was created.
ITBool LessThan(ITValue *object) Returns TRUE if the current object is less than the specified objects and the objects are comparable.
const ITString &Printable() Returns the value of the current object in a string equivalent to the one returned by the output function of the object.
ITBool SameType(ITValue *object) Returns TRUE if the specified object is of the same type as the current object.
ITBool SetNull() Sets the current object to a null value.
const ITTypeInfo &TypeOf() Returns the type information for the current object.