TBooleanField class
Boolean field class type.
Declaration
TBooleanField = class(TField)Inheritance
- TBooleanField
- TField
- TComponent
- TPersistent
- TObject
Description
TBooleanField is the field class used by
TDataset whenever
it needs to manage boolean data (
DataType equals
ftBoolean).
It overrides some properties and methods of
TField to be able to work with boolean data.
It should never be necessary to create an instance of TBooleanField manually, a field
of this class will be instantiated automatically for each boolean field when a dataset is opened.
See also
Properties
Value | public | Value of the field as a boolean value. |
DisplayValues | published | Textual representation of the true and false values. |
Methods
GetAsBoolean | protected | |
GetAsString | protected | |
GetAsVariant | protected | |
GetAsInteger | protected | |
GetDataSize | protected | |
GetDefaultWidth | protected | |
SetAsBoolean | protected | |
SetAsString | protected | |
SetAsInteger | protected | |
SetVarValue | protected | |
Create | public | Create a new instance of the TBooleanField class. |
Inherited
From TField (135)
AccessError Alignment AsAnsiString AsBCD AsBoolean AsBytes AsCurrency AsDateTime AsExtended AsFloat AsInteger AsLargeInt AsLongint AsLongWord Assign AssignValue AsSingle AsString AsUnicodeString AsUTF8String AsVariant AsWideString AttributeSet Bind Calculated CanModify Change CheckInactive CheckTypeSize Clear ConstraintErrorMessage CurValue CustomConstraint DataChanged DataSet DataSize DataType DefaultExpression Destroy DisplayLabel DisplayName DisplayText DisplayWidth EditMask EditMaskPtr FieldDef FieldKind FieldName FieldNo FocusControl FreeBuffers GetAsAnsiString GetAsBCD GetAsBytes GetAsCurrency GetAsDateTime GetAsExtended GetAsFloat GetAsLargeInt GetAsLongint GetAsLongWord GetAsSingle GetAsUnicodeString GetAsUTF8String GetAsWideString GetCanModify GetClassDesc GetCurValue GetData GetDisplayName GetIsNull GetNewValue GetOldValue GetParentComponent GetText HasConstraints HasParent ImportedConstraint Index IsBlob IsIndexField IsNull IsValidChar KeyFields Lookup LookupCache LookupDataSet LookupKeyFields LookupList LookupResultField NewValue Notification Offset OldValue OnChange OnGetText OnSetText OnValidate Origin ParentField PropertyChanged ProviderFlags ReadOnly ReadState RefreshLookupList Required SetAsAnsiString SetAsBCD SetAsBytes SetAsCurrency SetAsDateTime SetAsExtended SetAsFloat SetAsLargeInt SetAsLongint SetAsLongWord SetAsSingle SetAsUnicodeString SetAsUTF8String SetAsVariant SetAsWideString SetData SetDataset SetDataType SetFieldType SetNewValue SetParentComponent SetParentField SetSize SetText Size Text Validate ValidChars Visible
From TComponent (69)
_AddRef _Release BeforeDestruction CanObserve ChangeName ComObject ComponentCount ComponentIndex Components ComponentState ComponentStyle DefineProperties DesignInfo DestroyComponents Destroying ExecuteAction FindComponent FreeNotification FreeOnRelease GetChildOwner GetChildParent GetChildren GetDeltaStreams GetEnumerator GetIDsOfNames GetNamePath GetObservers GetOwner GetTypeInfo GetTypeInfoCount iicrGetComponent InsertComponent Invoke IsImplementorOf Loaded Loading Name ObserverAdded Observers OnGetDeltaStreams Owner PaletteCreated QueryInterface ReadDeltaState ReadDeltaStream ReferenceInterface RemoveComponent RemoveFreeNotification RemoveFreeNotifications SafeCallException SetAncestor SetChildOrder SetDesigning SetDesignInstance SetInline SetName SetSubComponent Tag ToString TToStringNameMode UpdateAction Updated UpdateRegistry Updating ValidateContainer ValidateInsert ValidateRename VCLComObject WriteState
From TPersistent (4)
AssignTo FPOAttachObserver FPODetachObserver FPONotifyObservers
From TObject (37)
AfterConstruction CheckDisposed ClassInfo ClassName ClassNameIs ClassParent ClassType CleanupInstance DefaultHandler DefaultHandlerStr Dispatch DispatchStr Disposed DisposeOf Equals FieldAddress Free FreeInstance GetDisposed GetHashCode GetInterface GetInterfaceByStr GetInterfaceEntry GetInterfaceEntryByStr GetInterfaceTable GetInterfaceWeak GetLastCastErrorInfo InheritsFrom InitInstance InstanceSize MethodAddress MethodName newinstance QualifiedClassName StringMessageTable SystemHasExtendedRTTI UnitName
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.