System.VarConv.VarConvert

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Delphi

function VarConvert: TVarType;

C++

extern DELPHI_PACKAGE System::Word __fastcall VarConvert(void);

Properties

Type Visibility Source Unit Parent
function public
System.VarConv.pas
System.VarConv.hpp
System.VarConv System.VarConv

Description

Returns the Variant type code for custom Variants that represent measurements.

Use VarConvert to obtain the variant type code for custom Variants that represent measurements. The Variant type codes for custom Variants are dynamically allocated when the application loads the unit that implements them. VarConvert allows the application to identify the Variant type code that is currently used for custom Variants that represent VarConvert custom Variants. This type code, however, may not match the type code used by another application that uses a different set of custom Variant types.

VarConvert custom Variants represent measurements (that is, a type of measurement units and the number of those units). The units must be registered measurement units such as those used by the ConvUtils unit. You can use the negation operator on VarConv variants, and use the addition, subtraction, multiplication, division, and comparison operators on a VarConv Variant with a real number. You can use the addition, subtraction, division, and comparison operators on two VarConv Variants.

VarConv custom Variants also support the following properties:

  • Value is the numeric portion (the number of units). (read/write)
  • Type is units. (read-only)
  • TypeName is the name of the units. (read-only).
  • Family is the conversion family of the units (the thing measured). (read-only).
  • FamilyName is the name of the conversion family. (read-only)

Depending on the Family, each Variant has a set of conversion properties with names of the form As<Unit>, where <Unit> is the name of another type of unit in the same conversion family.

See Also