TInterfaceField Members

The following tables list the members exposed by TInterfaceField.

	Name	Description
	FComponentStyle	FComponentStyle is the field of the ComponentStyle read-only property.

Protected Methods

	Name	Description
	_AddRef	Called when an application uses a component interface.
	_Release	Called when an application releases a component interface.
	AccessError	This is AccessError, a member of class TField.
	AssignTo	Copies the properties of an object to a destination object.
	Bind	This is Bind, a member of class TField.
	Change	This is Change, a member of class TField.
	ChangeName	Sets the private, internal storage for the Name property to the string passed in NewName.
	CheckInactive	This is CheckInactive, a member of class TField.
	CheckTypeSize	This is CheckTypeSize, a member of class TInterfaceField.
	CopyData	This is CopyData, a member of class TField.
	DataChanged	This is DataChanged, a member of class TField.
	DefineProperties	Designates methods for storing an object's unpublished data on a stream such as a form file.
	DefineProperties	Provides an interface for a method that reads and writes otherwise unpublished data.
	DefineProperties	Designates methods for storing an object's unpublished data on a stream such as a form file.
	FreeBuffers	This is FreeBuffers, a member of class TField.
	GetAsAnsiString	This is GetAsAnsiString, a member of class TField.
	GetAsBCD	This is GetAsBCD, a member of class TField.
	GetAsBoolean	This is GetAsBoolean, a member of class TField.
	GetAsByteArray	This is GetAsByteArray, a member of class TField.
	GetAsBytes	This is GetAsBytes, a member of class TField.
	GetAsCurrency	This is GetAsCurrency, a member of class TField.
	GetAsDateTime	This is GetAsDateTime, a member of class TField.
	GetAsExtended	This is GetAsExtended, a member of class TField.
	GetAsFloat	This is GetAsFloat, a member of class TField.
	GetAsInteger	This is GetAsInteger, a member of class TField.
	GetAsSQLTimeStamp	This is GetAsSQLTimeStamp, a member of class TField.
	GetAsString	This is GetAsString, a member of class TField.
	GetAsVariant	This is GetAsVariant, a member of class TInterfaceField.
	GetAsWideString	This is GetAsWideString, a member of class TField.
	GetCanModify	This is GetCanModify, a member of class TField.
	GetChildOwner	Returns the owner of a child component being read from a stream.
	GetChildParent	Returns the parent, or if there is no parent, returns the owner of a child component being read from a stream.
	GetChildren	Enumerates all child components.
	GetClassDesc	This is GetClassDesc, a member of class TField.
	GetDataSize	This is GetDataSize, a member of class TField.
	GetDefaultWidth	This is GetDefaultWidth, a member of class TField.
	GetFieldNo	This is GetFieldNo, a member of class TField.
	GetHasConstraints	This is GetHasConstraints, a member of class TField.
	GetIDsOfNames	Maps a single member and an optional set of argument names to a corresponding set of integer dispatch identifiers (dispIDs).
	GetIsNull	This is GetIsNull, a member of class TField.
	GetLookupListClass	This is GetLookupListClass, a member of class TField.
	GetOwner	Returns the owner of a component.
	GetOwner	Returns the owner of an object.
	GetSize	This is GetSize, a member of class TField.
	GetText	This is GetText, a member of class TField.
	GetTypeInfo	Retrieves the type information for an object.
	GetTypeInfoCount	Returns the number of type information interfaces that an object provides (either 0 or 1).
	GetValue	This is GetValue, a member of class TInterfaceField.
	GetWideText	This is GetWideText, a member of class TField.
	Invoke	Provides access to Automation properties and methods when the component wraps an Automation object.
	Loaded	Initializes the component after the form file has been read into memory.
	Notification	Forwards notification messages to all owned components.
	Notification	Forwards notification messages to all owned components.
	PaletteCreated	Responds when the component is created from the component palette.
	PropertyChanged	This is PropertyChanged, a member of class TField.
	QueryInterface	Returns a reference to a specified interface if the object supports that interface.
	ReadState	Reads the state of the component.
	ReadState	Reads the state of the component.
	SetAncestor	Clears or sets csAncestor state in the component's ComponentState property.
	SetAsAnsiString	This is SetAsAnsiString, a member of class TField.
	SetAsBCD	This is SetAsBCD, a member of class TField.
	SetAsBoolean	This is SetAsBoolean, a member of class TField.
	SetAsByteArray	This is SetAsByteArray, a member of class TField.
	SetAsBytes	This is SetAsBytes, a member of class TField.
	SetAsCurrency	This is SetAsCurrency, a member of class TField.
	SetAsDateTime	This is SetAsDateTime, a member of class TField.
	SetAsExtended	This is SetAsExtended, a member of class TField.
	SetAsFloat	This is SetAsFloat, a member of class TField.
	SetAsInteger	This is SetAsInteger, a member of class TField.
	SetAsSQLTimeStamp	This is SetAsSQLTimeStamp, a member of class TField.
	SetAsString	This is SetAsString, a member of class TField.
	SetAsVariant	This is SetAsVariant, a member of class TField.
	SetAsWideString	This is SetAsWideString, a member of class TField.
	SetAutoGenerateValue	This is SetAutoGenerateValue, a member of class TField.
	SetChildOrder	Sets the visual ordering of a child control.
	SetDataSet	This is SetDataSet, a member of class TField.
	SetDataType	This is SetDataType, a member of class TField.
	SetDesigning	Ensures that components inserted at design time have their design-mode flag set.
	SetDesignInstance	Ensures that components inserted at design time have their design-mode flag set.
	SetFieldKind	This is SetFieldKind, a member of class TField.
	SetInline	Sets the csInline bit of the component's ComponentState property
	SetName	Sets the value of the Name property.
	SetParentComponent	Sets the parent component.
	SetParentField	This is SetParentField, a member of class TField.
	SetSize	This is SetSize, a member of class TField.
	SetText	This is SetText, a member of class TField.
	SetValue	This is SetValue, a member of class TInterfaceField.
	SetVarValue	This is SetVarValue, a member of class TInterfaceField.
	SetWideText	This is SetWideText, a member of class TField.
	Updated	Clears the csUpdating state in the component's ComponentState property when the component finishes updating.
	UpdateRegistry	Provides the interface for a method that adds type library and version information to the Registry on components that implement COM interfaces.
	Updating	Sets the csUpdating state in the component's ComponentState property.
	ValidateContainer	Determines whether an object can be inserted into a container.
	ValidateInsert	Provides the interface for a method that validates an child component before it is inserted.
	ValidateRename	Ensures that renaming an owned component does not create name conflict.
	WriteState	Writes the state of the component.

Public Methods

	Name	Description
	_AddRef	Increments the reference count for this interface.
	_Release	Decrements the reference count for this interface.
	AfterConstruction	Responds after the last constructor has executed.
	Assign	Copies the contents of another, similar object.
	Assign	Copies the Value property from another field component or assigns another object to the field component.
	AssignValue	Sets the field value using one of the AsInteger, AsBoolean, AsString or AsFloat properties.
	BeforeDestruction	Performs any necessary actions before the first destructor is called.
	BeforeDestruction	Responds before the first destructor executes.
	ClassInfo	Returns a pointer to the runtime type information (RTTI) table for the object type.
	ClassName	Returns a string indicating the type of the object instance (as opposed to the type of the variable passed as an argument).
	ClassNameIs	Determines whether an object is of a specific type.
	ClassParent	Returns the type of the immediate ancestor of a class.
	ClassType	Returns the class reference for the object's class.
	CleanupInstance	Performs finalization on long strings, variants, and interface variables within a class.
	Clear	Sets the value of the field to NULL.
	Create	Creates and initializes an interface field component.
	DefaultHandler	Provides the interface for a method that processes message records.
	Destroy	Disposes of the component and its owned components.
	Destroy	Destroys the TPersistent instance and frees its memory.
	Destroy	Destroys an instance of TField.
	Destroy	Disposes of an object instance.
	DestroyComponents	Destroys all owned components.
	Destroying	Indicates that the component and its owned components are about to be destroyed.
	Dispatch	Calls message-handling methods for the object, based on the contents of the Message parameter.
	Equals	Checks if the current instance and the parameter are equal.
	ExecuteAction	Executes an action.
	FieldAddress	This is the overview for the FieldAddress method overload.
	FindComponent	Indicates whether a given component is owned by the component.
	FocusControl	Forces a form's focus to the first data-aware component associated with the field object.
	Free	Destroys an object and frees its associated memory, if necessary.
	FreeInstance	Deallocates memory allocated by a previous call to the System::TObject::NewInstance method.
	FreeNotification	Ensures that AComponent is notified that the component is going to be destroyed.
	FreeOnRelease	Frees the interface reference for components that were created from COM classes.
	GetComponent	Returns a reference to the component associated by the implementing class.
	GetData	Returns the unformatted data for the field.
	GetEnumerator	Returns a TComponent enumerator.
	GetHashCode	Returns an integer containing the hash code.
	GetInterface	Retrieves a specified interface.
	GetInterfaceEntry	Returns the entry for a specific interface implemented in a class.
	GetInterfaceTable	Returns a pointer to a structure containing all of the interfaces implemented by a given class.
	GetNamePath	Returns a string used by the Object Inspector.
	GetNamePath	Returns the name of the object as it appears in the Object Inspector.
	GetParentComponent	Returns the containing Component.
	GetParentComponent	Returns the component which directs the loading and saving of the field.
	HasParent	Verifies whether the component has a parent.
	HasParent	Returns true, indicating that field components act as part of a larger composite.
	InheritsFrom	Determines the relationship of two object types.
	InitInstance	Initializes a newly allocated object instance to all zeros and initializes the instance's virtual method table pointer.
	InsertComponent	Establishes the component as the owner of a specified component.
	InstanceSize	Returns the size in bytes of each instance of the object type.
	IsBlob	Indicates whether the field represents the data in a binary large object (BLOB) field.
	IsImplementorOf	Indicates whether the component implements a specified interface.
	IsValidChar	Indicates whether a particular character is valid for the field.
	MethodAddress	This is the overview for the MethodAddress method overload.
	MethodName	Returns the name of a class method by address.
	NewInstance	Allocates memory for an instance of an object type and returns a pointer to that new instance.
	QueryInterface	Returns a reference to a specified interface if the object supports that interface.
	ReferenceInterface	Establishes or removes internal links that cause this component to be notified when the implementer of a specified interface is destroyed.
	RefreshLookupList	Loads LookupList with all the values for LookupResultField that match distinct values of LookupKeyFields.
	RemoveComponent	Removes a specified component specified from the component's Components list.
	RemoveFreeNotification	Disables destruction notification that was enabled by FreeNotification
	SafeCallException	Handles exceptions in methods declared using the safecall calling convention.
	SafeCallException	Handles exceptions in methods declared using the safecall calling convention.
	SetData	Assigns unformatted data to the field.
	SetFieldType	Provides the interface for a method that can set the DataType for the field.
	SetParentComponent	Sets the parent component.
	SetSubComponent	Identifies whether the component is a subcomponent.
	ToString	Returns a string containing the class name.
	UnitName	Returns a string containing the unit name.
	UpdateAction	Updates the state of an action.
	Validate	Generates an OnValidate event.

Public Properties

	Name	Description
	AsAnsiString	This is AsAnsiString, a member of class TField.
	AsBCD	Represents the field's value as a TBcd value.
	AsBoolean	Represents the field's value as a boolean value.
	AsBytes	Represents the field's value as an array of bytes.
	AsCurrency	Represents the field's value as a Currency value.
	AsDateTime	Represents the field's value as a TDateTime value.
	AsExtended	This is AsExtended, a member of class TField.
	AsFloat	Represents the field's value as a double value.
	AsInteger	Represents the field's value as a 32-bit integer.
	AsSQLTimeStamp	Represents the field's value as a TSQLTimeStamp.
	AsString	Represents the field's value as a string (Delphi) or an AnsiString (C++).
	AsVariant	Represents the Value of the field as a Variant.
	AsWideString	This is AsWideString, a member of class TField.
	AttributeSet	Specifies the name of an attribute set in the data dictionary to apply to the field component.
	Calculated	Determines whether the value of the field is calculated by the OnCalcFields event handler of its dataset.
	CanModify	Specifies whether a field can be modified.
	ComObject	Specifies the interface reference implemented by the component.
	ComponentCount	Indicates the number of components owned by the component.
	ComponentIndex	Indicates the position of the component in its owner's Components property array.
	Components	Lists all components owned by the component.
	ComponentState	Describes the current state of the component, indicating when a component needs to avoid certain actions.
	ComponentStyle	Governs the behavior of the component.
	CurValue	Represents the current value of the field component including changes made by other users of the database.
	DataSet	Identifies the dataset to which a field component belongs.
	DataSize	Indicates the amount of memory needed to store a field component's value.
	DataType	Identifies the data type of the field component.
	DesignInfo	Contains information used by the Form designer.
	DisplayName	Represents the name of the field for display purposes.
	DisplayText	Represents the field's value as it is displayed in a data-aware control.
	EditMask	Contains a mask that restricts the data that can be entered into a data field.
	EditMaskPtr	Provides read-only access to the EditMask property.
	FieldNo	Indicates the ordinal position of the field's column in the underlying table or query result.
	FullName	Indicates the field name qualified by the full name of the parent field, if any.
	IsIndexField	Indicates whether a field is an index field.
	IsNull	Indicates whether the field has a value assigned to it.
	Lookup	Determines whether the field is specified as a lookup field.
	LookupList	Indicates a cache of values from the LookupDataSet indexed by a set of values from the KeyFields property.
	NewValue	Represents the current value of the field component including pending cached updates.
	Offset	Indicates the number of bytes added to the end of the current record buffer in the dataset for storing cached values (for calculated fields or BLOB fields).
	OldValue	Represents the original value of the field (as a Variant).
	Owner	Indicates the component that is responsible for streaming and freeing this component.
	ParentField	Specifies the TObjectField object from which this field is derived.
	Size	Indicates the size used in the definition of the physical database field for data types that support different sizes.
	Text	Contains the string to display in a data-aware control when the field is in edit mode.
	ValidChars	Specifies the characters that can be included in the text representation of the field's value.
	Value	Represents the data in an interface field component.
	VCLComObject	Represents information used internally by components that support COM.

Published Events

	Name	Description
	OnChange	Occurs immediately after the data in the field is written to the record buffer.
	OnGetText	Occurs when the DisplayText or Text properties of the field are referenced.
	OnSetText	Occurs when the Text property is assigned a value.
	OnValidate	Occurs just before the data is written to the record buffer.

Published Properties

	Name	Description
	Alignment	Determines how the field's data is displayed within a data-aware control.
	AutoGenerateValue	Indicates whether the field values can be generated by the server rather than entered by the user.
	ConstraintErrorMessage	Specifies a customized error message that appears when the user tries to set a value that violates the data constraints of the field.
	CustomConstraint	Specifies an SQL string the enforces any application-specific constraints on the field's value.
	DefaultExpression	Specifies an SQL expression that is assigned to the field if the user does not provide a value.
	DisplayLabel	Contains the text to display in the corresponding column heading of a data grid.
	DisplayWidth	Specifies the number of characters that should be used to display a field's value by a cooperating data-aware control.
	FieldKind	Indicates whether a field represents a column in a dataset, a calculated field, or a lookup field.
	FieldName	Indicates the name of the physical column in the underlying table or query result to which a field component is bound.
	HasConstraints	Indicates whether field values are constrained.
	ImportedConstraint	Represents an SQL clause that enforces constraints stored on the server.
	Index	Specifies the field component's index in the Fields property of the dataset.
	KeyFields	Identifies the field or fields in the dataset that must be matched in a lookup dataset when doing a lookup.
	LookupCache	Determines whether the values of a lookup field are cached or looked up dynamically every time the current record in the dataset changes.
	LookupDataSet	Identifies the dataset used to look up field values.
	LookupKeyFields	Identifies the field or fields in the lookup dataset to match when doing a lookup.
	LookupResultField	Identifies the field from the lookup dataset whose value becomes the Value property of the field component.
	Name	Specifies the name of the component as referenced in code.
	Origin	Indicates the name of the field in its original database table.
	ProviderFlags	Specifies how a provider uses the field value when applying updates.
	ReadOnly	Determines whether the field can be modified.
	Required	Specifies whether a nonblank value for a field is required.
	Tag	Stores an integer value as part of a component.
	Visible	Determines whether the field appears in a data grid.

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