Page 168 - DCAP404 _Object Oriented Programming

Unit 8: Type Conversion

to the source class and is passed to the destination class for conversion. Therefore the conversion Notes
constructor must be placed in the destination class.
The following Figure 8.1 illustrates the above two approaches.

Figure 8.1: Conversions between Objects

The Table 8.1 summarizes all the three conversions. It shows that the conversion from a class to
any other type (or any other class) makes use of a casting operator in the source class. To perform
the conversion from any other type or class to a class type, a constructor is used in the
destination class.

Table 8.1

When a conversion using a constructor is performed in the destination class, we must be able to
access the data members of the object sent (by the source class) as an argument.

Task ’Since data members of the source class are private, we must use special access
functions in the source class to facilitate its data flow to the destination class.’ Explain this
statement.

Consider the following example of an inventory of products in a store. One way of keeping
record of the details of the products is to record their code number, total items in the stock and
the cost of each item. Alternatively we could just specify the item code and the value of the item

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