TDoubleLinkedBufIndex class

In unit BufDataset

Implements an index using a doubly-linked list.

Declaration

pascal

TDoubleLinkedBufIndex = class(TBufIndex)

Inheritance

TDoubleLinkedBufIndex
TBufIndex
TObject

Description

TDoubleLinkedBufIndex is a TBufIndex descendant that implements an index using a doubly-linked list. Nodes in the doubly-linked list are implemented using the TBufRecLinkItem record type and the PBufRecLinkItem pointer type. TDoubleLinkedBufIndex provides two sentinel nodes that represent the first and last items in the linked list.

TDoubleLinkedBufIndex is the type used to implement the default index ('DEFAULT_ORDER') in TBufDataset.

Methods

`GetBookmarkSize`	protected	Gets the value for the BookmarkSize property.
`GetCurrentBuffer`	protected	Gets the value for the CurrentBuffer property.
`GetCurrentRecord`	protected	Gets the value for the CurrentRecord property.
`GetIsInitialized`	protected	Gets the value for the IsInitialized property.
`GetSpareBuffer`	protected	Gets the value for the SpareBuffer property.
`GetSpareRecord`	protected	Gets the value for the SpareRecord property.
`GetRecNo`	protected	Gets the value for the RecNo property.
`SetRecNo`	protected	Sets the value for the RecNo property.
`ScrollBackward`	public	Scrolls the index toward the beginning of the index.
`ScrollForward`	public	Scrolls the index towards the end of the index.
`GetCurrent`	public	Gets the record buffer for the current record in the dataset.
`ScrollFirst`	public	Scrolls to the first entry in the index.
`ScrollLast`	public	Scrolls to the last entry in the index.
`GetRecord`	public	Gets prior/next record relative to the specified bookmark.
`SetToFirstRecord`	public	Sets the index to the first record in the index order.
`SetToLastRecord`	public	Sets the index to the last record in the index order.
`StoreCurrentRecord`	public	Stores the record buffer for the current record.
`RestoreCurrentRecord`	public	Restores the stored record buiffer to the current record.
`CanScrollForward`	public	Indicates if the index can be scrolled towards the end of the index.
`DoScrollForward`	public	Implements actions needed to scroll forward using the index.
`StoreCurrentRecIntoBookmark`	public
`StoreSpareRecIntoBookmark`	public
`GotoBookmark`	public	Navigates the index to the specified Bookmark.
`CompareBookmarks`	public	Gets the relative order for the specified Bookmarks.
`SameBookmarks`	public	Compares Bookmark values for ordering in the index.
`InitialiseIndex`	public	Initializes the index.
`InitialiseSpareRecord`	public	Initializes the spare record in the index.
`ReleaseSpareRecord`	public	Releases the spare record in the index.
`BeginUpdate`	public
`AddRecord`	public	Adds a record to the index.
`InsertRecordBeforeCurrentRecord`	public	Inserts a record prior to the current record in the index.
`RemoveRecordFromIndex`	public	Removes the record at the specified Bookmark from the index.
`OrderCurrentRecord`	public
`EndUpdate`	public

Fields

`FLastRecBuf`	public
`FFirstRecBuf`	public
`FNeedScroll`	public

Inherited

From TBufIndex (9)

BookmarkSize BookmarkValid Create CurrentBuffer CurrentRecord IsInitialized RecNo SpareBuffer SpareRecord

From TObject (41)

AfterConstruction BeforeDestruction CheckDisposed ClassInfo ClassName ClassNameIs ClassParent ClassType CleanupInstance DefaultHandler DefaultHandlerStr Destroy Dispatch DispatchStr Disposed DisposeOf Equals FieldAddress Free FreeInstance GetDisposed GetHashCode GetInterface GetInterfaceByStr GetInterfaceEntry GetInterfaceEntryByStr GetInterfaceTable GetInterfaceWeak GetLastCastErrorInfo InheritsFrom InitInstance InstanceSize MethodAddress MethodName newinstance QualifiedClassName SafeCallException StringMessageTable SystemHasExtendedRTTI ToString UnitName

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.