Creating a Class to Enable the Custom Variant Type

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Custom variants work by using a special helper class that indicates how variants of the custom type can perform standard operations. You create this helper class by writing a descendant of System.Variants.TCustomVariantType. This involves overriding the appropriate virtual methods of TCustomVariantType.

The following topics provide details on how to implement and use a TCustomVariantType descendant:

• Enabling casting
• Implementing binary operations
• Implementing comparison operations
• Implementing unary operations
• Copying and clearing custom variants
• Loading and saving custom variant values
• Using the TCustomVariantType descendant

See Also

• Defining Custom Variants
• Writing Utilities to Work with a Custom Variant Type
• Storing the Data of a Custom Variant Type
• Supporting Properties and Methods in Custom Variants