Data.DB.TField.AssignValue

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Delphi

procedure AssignValue(const Value: TVarRec); virtual;

C++

virtual void __fastcall AssignValue(const System::TVarRec &Value);

Properties

Type Visibility Source Unit Parent
procedure
function
public
Data.DB.pas
Data.DB.hpp
Data.DB TField

Description

Sets the field value using one of the AsInteger, AsBoolean, AsString or AsFloat properties.

Use AssignValue to assign a value to a field and, in Delphi, that comes from an array of const. AssignValue uses an As property for the assignment based on the type of the Value parameter:



Value As... property used

vtInteger

AsInteger

vtBoolean

AsBoolean

vtChar

AsString

vtExtended

AsFloat

vtString

AsString

vtPChar

AsString

vtAnsiString

AsString

vtCurrency

AsCurrency

vtVariant

AsVariant



If Value is not one of the types in the table, but is of type TObject or a TObject descendant, AssignValue uses the Assign method to assign the value to the field.

AssignValue exists primarily for internal use. In C++ applications and components, use the TField::Value property instead. In most Delphi situations, you should use the data type-specific assignment properties like AsString and AsInteger. In cases where a component or an application must be able to make field assignments from untyped arrays, the syntax for AssignValue looks like that below. In this example, a custom data class uses AssignValue in a member method named SetFieldValues to assign values to multiple fields. The values for the field assignments come from an untyped array.



procedure TCustomDataClass.SetFieldValues(Values: array of const);
var
i: Integer;
begin
for i := 0 to High(Values) do
Fields[i].AssignValue(Values[i]);
end;



See Also