Data.DB.TField.AssignValue
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;