RAD Studio |  |

typeid

Category

Operators, C++-Specific Keywords

Syntax

Copy Code

    typeid( expression )
    typeid( type-name )

Description

You can use typeid to get runtime identification of types and expressions. A call to typeid returns a reference to an object of type const type_info. The returned object represents the type of the typeid operand.

If the typeid operand is a dereferenced pointer or a reference to a polymorphic type, typeid returns the dynamic type of the actual object pointed or referred to. If the operand is non-polymorphic, typeid returns an object that represents the static type.

You can use the typeid operator with fundamental data types as well as user-defined types.

When the typeid operand is a Delphi class object/reference, typeid returns the static rather than runtime type.

If the typeid operand is a dereferenced NULL pointer, the Bad_typeid exception is thrown.

Copyright(C) 2009 Embarcadero Technologies, Inc. All Rights Reserved.
What do you think about this topic? Send feedback!