TDADatasetFieldCollection
Overview
TDADatasetFieldCollection is a container for TDAField objects that represent the physical fields underlying a dataset or calculated fields in TDASchema.
Location
- Unit: uDASchema.pas
- Ancestry: TOwnedCollection | TSearcheableCollection | TSearcheableCollectionCached | TSearcheableInterfacedCollection | TDACustomFieldCollection | TDAFieldCollection | TDADatasetFieldCollection
constructor Create (TDADataset)
Creates a new instance.
constructor Create(aOwner: TDADataset)
Parameters:
- aOwner: Owner
constructor Create (TPersistent) (declared in TDAFieldCollection)
Creates a new instance.
constructor Create(aOwner: TPersistent)
Parameters:
- aOwner: owner
constructor Create (TPersistent, TDAFieldClass) (declared in TDACustomFieldCollection)
Creates a new instance.
constructor Create(aOwner: TPersistent; aFieldClass: TDAFieldClass)
Parameters:
- aOwner: owner
- aFieldClass: field class
constructor Create (TPersistent, TCollectionItemClass) (declared in TSearcheableCollectionCached)
Initializes the collection with the supplied parameters.
constructor Create(AOwner: TPersistent; ItemClass: TCollectionItemClass)
Parameters:
- AOwner: owner
- ItemClass: item class
Add reintroduce overload (declared in TDACustomFieldCollection)
Creates new TDAField and add it to collection
function Add: TDAField
Add (string, TDADataType, Integer): TDACustomField overload (declared in TDACustomFieldCollection)
Creates new TDAField, fills with specified properties and adds it to collection
function Add(const aName: string; aType: TDADataType; aSize: Integer): TDACustomField
Parameters:
- aName: field name
- aType: field type
- aSize: field size
Assign override (declared in TDACustomFieldCollection)
Calls AssignFieldCollection if source is TDACustomFieldCollection
procedure Assign(Source: TPersistent)
Parameters:
- Source: Instance whose properties will be copied
AssignFieldCollection (declared in TDACustomFieldCollection)
Copies the contents of another collection to the object where the method is executed.
procedure AssignFieldCollection(Source: TDACustomFieldCollection)
Parameters:
- Source: Instance whose properties will be copied
Bind (TDataset) overload (declared in TDACustomFieldCollection)
Binds child fields with aDataset
procedure Bind(aDataset: TDataset)
Parameters:
- aDataset: dataset
Bind (IDASQLCommandNativeObject) overload (declared in TDACustomFieldCollection)
Binds child fields with aNativeObject
procedure Bind(aNativeObject: IDASQLCommandNativeObject)
Parameters:
- aNativeObject: native object
CloneItem (declared in TSearcheableCollection)
Inserts a copy of an item and names it "Copy nn of " of the cloned item name.
function CloneItem(iIndex: Integer): Integer
Parameters:
- iIndex: position.
DataDictionary (declared in TDACustomFieldCollection)
Gets/sets the DataDictionary property.
property DataDictionary: IDADataDictionary read write
FieldByName (string): TDACustomField (declared in TDACustomFieldCollection)
Finds a field based on its name. If the specified field does not exist, FieldByName raises an exception.
function FieldByName(const aName: string): TDACustomField
Parameters:
- aName: name of the searched field
FieldByName (string): TDAField reintroduce (declared in TDAFieldCollection)
Returns an item with the specified name. If no matching field is defined, an exception will be raised.
function FieldByName(const aName: string): TDAField
Parameters:
- aName:
FieldEventsDisabled (declared in TDACustomFieldCollection)
Allows to process events in child items.
property FieldEventsDisabled: Boolean read write
Fields (declared in TDACustomFieldCollection)
Provides access to specific field.
property Fields[Index: Integer]: TDACustomField read write
Fields (declared in TDAFieldCollection)
This indexer property gives access to the individual fields contained in the collection.
property Fields[Index: Integer]: TDAField read write
FindField (string): TDACustomField (declared in TDACustomFieldCollection)
Returns an item with the specified name.
function FindField(const aName: string): TDACustomField
Parameters:
- aName: name of the searched field
FindField (string): TDAField (declared in TDAFieldCollection)
Returns an item with the specified name.
function FindField(const aName: string): TDAField
Parameters:
- aName:
FindItem override (declared in TSearcheableCollectionCached)
Finds the first occurrence of the item with the supplied name. Search is case-insensitive.
function FindItem(const aName: string): TCollectionItem
Parameters:
- aName: the supplied name
FindUniqueName (declared in TSearcheableCollection)
Returns the supplied name if the item with that name is absent in the collection or adds a number to it and sequentially increments it until the result is unique.
function FindUniqueName(const iBaseName: string): string
Parameters:
- iBaseName: the supplied name
FindUniqueNameEx (declared in TSearcheableCollection)
Does the same as FindUniqueName, but uses a template with a numeric parameter as second argument, it should be compatible with the Delphi Format function.
function FindUniqueNameEx(const iBaseName: string; const iNumberedName: string): string
Parameters:
- iBaseName: the supplied name
- iNumberedName: numeric parameter
GetCount protected (declared in TSearcheableInterfacedCollection)
Does nothing, should be implemented in the descendant.
function GetCount: Integer
GetDataDictionary protected override
Returns schema's DataDictionary
function GetDataDictionary: IDADataDictionary
GetDefaultItem (declared in TSearcheableCollection)
Looks for the first occurrence of the item that has a boolean property with the name "Default" and the value true. Raises an exception if no such item can be found.
function GetDefaultItem: TCollectionItem
GetItemDefault protected dynamic (declared in TSearcheableCollection)
Returns default item's name
function GetItemDefault(anItem: TCollectionItem): Boolean
Parameters:
- anItem: given item
GetItemName protected override (declared in TDACustomFieldCollection)
Gets the name of the specified item.
function GetItemName(anItem: TCollectionItem): string
Parameters:
- anItem: the specified item.
IsCompatibleV4 (declared in TDACustomFieldCollection)
Specifies DA4 compatible mode.
property IsCompatibleV4: Boolean read write
ItemByName (declared in TSearcheableCollection)
Returns an item with the specified name.
function ItemByName(const aName: string): TCollectionItem
Parameters:
- aName: fClientFields
ItemName protected virtual (declared in TSearcheableCollection)
Returns the string "item".
function ItemName: string
MergeDataDictionaries protected override
Returns state of owner schema.
function MergeDataDictionaries: Boolean
MoveItem (declared in TSearcheableCollection)
Moves the item from one position to another. Checks boundaries.
procedure MoveItem(iFromIndex: Integer; iToIndex: Integer)
Parameters:
- iFromIndex: old index
- iToIndex: new index
Notify protected override (declared in TSearcheableCollectionCached)
Notifies about the adding or removal of an item if the event handler is assigned. If an item with an empty name is added and items without name are not allowed, it sets the name to "Item" plus number.
procedure Notify(Item: TCollectionItem; Action: TCollectionNotification)
Parameters:
- Item: given item
- Action: action
OnFieldAfterUpdate (declared in TDACustomFieldCollection)
This event is fired if field was updated
property OnFieldAfterUpdate: TDAFieldNotifyEvent read write
delegate: procedure OnFieldAfterUpdate(Sender: TDACustomField)
OnFieldBeforeUpdate (declared in TDACustomFieldCollection)
This event is fired before field was updated
property OnFieldBeforeUpdate: TDAFieldNotifyEvent read write
delegate: procedure OnFieldBeforeUpdate(Sender: TDACustomField)
OnItemRemoved (declared in TSearcheableCollection)
Event handler for removing an item.
property OnItemRemoved: TDAItemRemovedEvent read write
delegate: procedure OnItemRemoved(aSender: TObject; const aName: string)
OnItemRenamed (declared in TSearcheableCollection)
Event handler for renaming an item.
property OnItemRenamed: TDAItemRenamedEvent read write
delegate: procedure OnItemRenamed(aSender: TObject; const aOldName: string; const aNewName: string)
PrimaryKeyFieldCount (declared in TDACustomFieldCollection)
Calculates number of fields that have InPrimaryKey = True;
property PrimaryKeyFieldCount: Integer read
QueryInterface protected stdcall (declared in TSearcheableInterfacedCollection)
Returns a reference to a specified interface if the object supports that interface. This is one of the methods introduced by the IUnknown interface.
function QueryInterface(const IID: TGUID; out Obj: ): HResult
Parameters:
- IID: Identifier of the interface to return
- Obj: Variable to store the returned interface reference to
SetItemName protected override (declared in TDACustomFieldCollection)
Sets a new name for the specified item.
function SetItemName(anItem: TCollectionItem; const aName: string): string
Parameters:
- anItem: item
- aName: name
TriggerOnItemRemoved override (declared in TSearcheableCollectionCached)
Calls the event handler if it was assigned.
procedure TriggerOnItemRemoved(const iName: string)
Parameters:
- iName: item name
TriggerOnItemRenamed override (declared in TSearcheableCollectionCached)
Calls the event handler if it was assigned.
procedure TriggerOnItemRenamed(const iOldName: string; const iNewName: string)
Parameters:
- iOldName: old name
- iNewName: new name
Unbind (declared in TDACustomFieldCollection)
Unbinds early binded collections
procedure Unbind
DataDictionary (declared in TDACustomFieldCollection)
Gets/sets the DataDictionary property.
property DataDictionary: IDADataDictionary read write
FieldEventsDisabled (declared in TDACustomFieldCollection)
Allows to process events in child items.
property FieldEventsDisabled: Boolean read write
Fields (declared in TDACustomFieldCollection)
Provides access to specific field.
property Fields[Index: Integer]: TDACustomField read write
Fields (declared in TDAFieldCollection)
This indexer property gives access to the individual fields contained in the collection.
property Fields[Index: Integer]: TDAField read write
IsCompatibleV4 (declared in TDACustomFieldCollection)
Specifies DA4 compatible mode.
property IsCompatibleV4: Boolean read write
PrimaryKeyFieldCount (declared in TDACustomFieldCollection)
Calculates number of fields that have InPrimaryKey = True;
property PrimaryKeyFieldCount: Integer read
constructor Create (TDADataset)
Creates a new instance.
constructor Create(aOwner: TDADataset)
Parameters:
- aOwner: Owner
constructor Create (TPersistent) (declared in TDAFieldCollection)
Creates a new instance.
constructor Create(aOwner: TPersistent)
Parameters:
- aOwner: owner
constructor Create (TPersistent, TDAFieldClass) (declared in TDACustomFieldCollection)
Creates a new instance.
constructor Create(aOwner: TPersistent; aFieldClass: TDAFieldClass)
Parameters:
- aOwner: owner
- aFieldClass: field class
constructor Create (TPersistent, TCollectionItemClass) (declared in TSearcheableCollectionCached)
Initializes the collection with the supplied parameters.
constructor Create(AOwner: TPersistent; ItemClass: TCollectionItemClass)
Parameters:
- AOwner: owner
- ItemClass: item class
Add reintroduce overload (declared in TDACustomFieldCollection)
Creates new TDAField and add it to collection
function Add: TDAField
Add (string, TDADataType, Integer): TDACustomField overload (declared in TDACustomFieldCollection)
Creates new TDAField, fills with specified properties and adds it to collection
function Add(const aName: string; aType: TDADataType; aSize: Integer): TDACustomField
Parameters:
- aName: field name
- aType: field type
- aSize: field size
Assign override (declared in TDACustomFieldCollection)
Calls AssignFieldCollection if source is TDACustomFieldCollection
procedure Assign(Source: TPersistent)
Parameters:
- Source: Instance whose properties will be copied
AssignFieldCollection (declared in TDACustomFieldCollection)
Copies the contents of another collection to the object where the method is executed.
procedure AssignFieldCollection(Source: TDACustomFieldCollection)
Parameters:
- Source: Instance whose properties will be copied
Bind (TDataset) overload (declared in TDACustomFieldCollection)
Binds child fields with aDataset
procedure Bind(aDataset: TDataset)
Parameters:
- aDataset: dataset
Bind (IDASQLCommandNativeObject) overload (declared in TDACustomFieldCollection)
Binds child fields with aNativeObject
procedure Bind(aNativeObject: IDASQLCommandNativeObject)
Parameters:
- aNativeObject: native object
CloneItem (declared in TSearcheableCollection)
Inserts a copy of an item and names it "Copy nn of " of the cloned item name.
function CloneItem(iIndex: Integer): Integer
Parameters:
- iIndex: position.
FieldByName (string): TDACustomField (declared in TDACustomFieldCollection)
Finds a field based on its name. If the specified field does not exist, FieldByName raises an exception.
function FieldByName(const aName: string): TDACustomField
Parameters:
- aName: name of the searched field
FieldByName (string): TDAField reintroduce (declared in TDAFieldCollection)
Returns an item with the specified name. If no matching field is defined, an exception will be raised.
function FieldByName(const aName: string): TDAField
Parameters:
- aName:
FindField (string): TDACustomField (declared in TDACustomFieldCollection)
Returns an item with the specified name.
function FindField(const aName: string): TDACustomField
Parameters:
- aName: name of the searched field
FindField (string): TDAField (declared in TDAFieldCollection)
Returns an item with the specified name.
function FindField(const aName: string): TDAField
Parameters:
- aName:
FindItem override (declared in TSearcheableCollectionCached)
Finds the first occurrence of the item with the supplied name. Search is case-insensitive.
function FindItem(const aName: string): TCollectionItem
Parameters:
- aName: the supplied name
FindUniqueName (declared in TSearcheableCollection)
Returns the supplied name if the item with that name is absent in the collection or adds a number to it and sequentially increments it until the result is unique.
function FindUniqueName(const iBaseName: string): string
Parameters:
- iBaseName: the supplied name
FindUniqueNameEx (declared in TSearcheableCollection)
Does the same as FindUniqueName, but uses a template with a numeric parameter as second argument, it should be compatible with the Delphi Format function.
function FindUniqueNameEx(const iBaseName: string; const iNumberedName: string): string
Parameters:
- iBaseName: the supplied name
- iNumberedName: numeric parameter
GetCount protected (declared in TSearcheableInterfacedCollection)
Does nothing, should be implemented in the descendant.
function GetCount: Integer
GetDataDictionary protected override
Returns schema's DataDictionary
function GetDataDictionary: IDADataDictionary
GetDefaultItem (declared in TSearcheableCollection)
Looks for the first occurrence of the item that has a boolean property with the name "Default" and the value true. Raises an exception if no such item can be found.
function GetDefaultItem: TCollectionItem
GetItemDefault protected dynamic (declared in TSearcheableCollection)
Returns default item's name
function GetItemDefault(anItem: TCollectionItem): Boolean
Parameters:
- anItem: given item
GetItemName protected override (declared in TDACustomFieldCollection)
Gets the name of the specified item.
function GetItemName(anItem: TCollectionItem): string
Parameters:
- anItem: the specified item.
ItemByName (declared in TSearcheableCollection)
Returns an item with the specified name.
function ItemByName(const aName: string): TCollectionItem
Parameters:
- aName: fClientFields
ItemName protected virtual (declared in TSearcheableCollection)
Returns the string "item".
function ItemName: string
MergeDataDictionaries protected override
Returns state of owner schema.
function MergeDataDictionaries: Boolean
MoveItem (declared in TSearcheableCollection)
Moves the item from one position to another. Checks boundaries.
procedure MoveItem(iFromIndex: Integer; iToIndex: Integer)
Parameters:
- iFromIndex: old index
- iToIndex: new index
Notify protected override (declared in TSearcheableCollectionCached)
Notifies about the adding or removal of an item if the event handler is assigned. If an item with an empty name is added and items without name are not allowed, it sets the name to "Item" plus number.
procedure Notify(Item: TCollectionItem; Action: TCollectionNotification)
Parameters:
- Item: given item
- Action: action
QueryInterface protected stdcall (declared in TSearcheableInterfacedCollection)
Returns a reference to a specified interface if the object supports that interface. This is one of the methods introduced by the IUnknown interface.
function QueryInterface(const IID: TGUID; out Obj: ): HResult
Parameters:
- IID: Identifier of the interface to return
- Obj: Variable to store the returned interface reference to
SetItemName protected override (declared in TDACustomFieldCollection)
Sets a new name for the specified item.
function SetItemName(anItem: TCollectionItem; const aName: string): string
Parameters:
- anItem: item
- aName: name
TriggerOnItemRemoved override (declared in TSearcheableCollectionCached)
Calls the event handler if it was assigned.
procedure TriggerOnItemRemoved(const iName: string)
Parameters:
- iName: item name
TriggerOnItemRenamed override (declared in TSearcheableCollectionCached)
Calls the event handler if it was assigned.
procedure TriggerOnItemRenamed(const iOldName: string; const iNewName: string)
Parameters:
- iOldName: old name
- iNewName: new name
Unbind (declared in TDACustomFieldCollection)
Unbinds early binded collections
procedure Unbind
OnFieldAfterUpdate (declared in TDACustomFieldCollection)
This event is fired if field was updated
property OnFieldAfterUpdate: TDAFieldNotifyEvent read write
delegate: procedure OnFieldAfterUpdate(Sender: TDACustomField)
OnFieldBeforeUpdate (declared in TDACustomFieldCollection)
This event is fired before field was updated
property OnFieldBeforeUpdate: TDAFieldNotifyEvent read write
delegate: procedure OnFieldBeforeUpdate(Sender: TDACustomField)
OnItemRemoved (declared in TSearcheableCollection)
Event handler for removing an item.
property OnItemRemoved: TDAItemRemovedEvent read write
delegate: procedure OnItemRemoved(aSender: TObject; const aName: string)
OnItemRenamed (declared in TSearcheableCollection)
Event handler for renaming an item.
property OnItemRenamed: TDAItemRenamedEvent read write
delegate: procedure OnItemRenamed(aSender: TObject; const aOldName: string; const aNewName: string)