TDADatasetRelationshipCollection

Overview

The TDADatasetRelationshipCollection stores the collection of master-detail relationships for the dataset in the schema. The collection can be accessed via the TDASchema.RelationShips property. Usually, you will not need to use this class directly.

Location

 

constructor Create (TComponent)

Creates a new instance.

constructor Create(aOwner: TComponent)

Parameters:

  • aOwner: owner

constructor Create (TPersistent, TCollectionItemClass)    (declared in TSearcheableCollection)

Initializes the collection with the supplied parameters.

constructor Create(AOwner: TPersistent; ItemClass: TCollectionItemClass)

Parameters:

  • AOwner: owner
  • ItemClass: item class

Add  overload

Adds a new master-detail relation.

function Add: TDADatasetRelationship

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.

FindItem  virtual    (declared in TSearcheableCollection)

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

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

GetDetails

Returns the list of master-detail relationships for the given dataset.

procedure GetDetails(const aMasterDatasetName: string; aList: TDADatasetRelationshipList)

Parameters:

  • aMasterDatasetName: name for the master dataset
  • aList: destination

GetItemDefault  protected dynamic    (declared in TSearcheableCollection)

Returns default item's name

function GetItemDefault(anItem: TCollectionItem): boolean

Parameters:

  • anItem: given item

GetItemName  protected override

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

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 TSearcheableCollection)

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

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)

RelationShipByName

Returns a relationship by name, if it exists.

function RelationShipByName(const aName: string): TDADatasetRelationship

Parameters:

  • aName: the specified name.

RelationshipExists

Checks for the existence of a relationship with the given parameters.

function RelationshipExists(const aMasterDatasetName: string; const aDetailDatasetName: string; const aMasterFields: string; const aDetailFields: string): Boolean

Parameters:

  • aMasterDatasetName: name for the master dataset
  • aDetailDatasetName: name for the detail dataset
  • aMasterFields: one or more fields in a master table
  • aDetailFields: one or more fields in a detail table

Relationships

Returns the list of objects that represents the master-detail relationship between datasets.

property Relationships[Index: integer]: TDADatasetRelationship read write

SetItemName  protected override

Sets a new name for the specified item.

function SetItemName(anItem: TCollectionItem; const aName: string): string

Parameters:

  • anItem: item
  • aName: name

TriggerOnItemRemoved  virtual    (declared in TSearcheableCollection)

Calls the event handler if it was assigned.

procedure TriggerOnItemRemoved(const iName: string)

Parameters:

  • iName: item name

TriggerOnItemRenamed  virtual    (declared in TSearcheableCollection)

Calls the event handler if it was assigned.

procedure TriggerOnItemRenamed(const iOldName: string; const iNewName: string)

Parameters:

  • iOldName: old name
  • iNewName: new name

 

Relationships

Returns the list of objects that represents the master-detail relationship between datasets.

property Relationships[Index: integer]: TDADatasetRelationship read write

 

constructor Create (TComponent)

Creates a new instance.

constructor Create(aOwner: TComponent)

Parameters:

  • aOwner: owner

constructor Create (TPersistent, TCollectionItemClass)    (declared in TSearcheableCollection)

Initializes the collection with the supplied parameters.

constructor Create(AOwner: TPersistent; ItemClass: TCollectionItemClass)

Parameters:

  • AOwner: owner
  • ItemClass: item class

Add  overload

Adds a new master-detail relation.

function Add: TDADatasetRelationship

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.

FindItem  virtual    (declared in TSearcheableCollection)

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

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

GetDetails

Returns the list of master-detail relationships for the given dataset.

procedure GetDetails(const aMasterDatasetName: string; aList: TDADatasetRelationshipList)

Parameters:

  • aMasterDatasetName: name for the master dataset
  • aList: destination

GetItemDefault  protected dynamic    (declared in TSearcheableCollection)

Returns default item's name

function GetItemDefault(anItem: TCollectionItem): boolean

Parameters:

  • anItem: given item

GetItemName  protected override

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

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 TSearcheableCollection)

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

RelationShipByName

Returns a relationship by name, if it exists.

function RelationShipByName(const aName: string): TDADatasetRelationship

Parameters:

  • aName: the specified name.

RelationshipExists

Checks for the existence of a relationship with the given parameters.

function RelationshipExists(const aMasterDatasetName: string; const aDetailDatasetName: string; const aMasterFields: string; const aDetailFields: string): Boolean

Parameters:

  • aMasterDatasetName: name for the master dataset
  • aDetailDatasetName: name for the detail dataset
  • aMasterFields: one or more fields in a master table
  • aDetailFields: one or more fields in a detail table

SetItemName  protected override

Sets a new name for the specified item.

function SetItemName(anItem: TCollectionItem; const aName: string): string

Parameters:

  • anItem: item
  • aName: name

TriggerOnItemRemoved  virtual    (declared in TSearcheableCollection)

Calls the event handler if it was assigned.

procedure TriggerOnItemRemoved(const iName: string)

Parameters:

  • iName: item name

TriggerOnItemRenamed  virtual    (declared in TSearcheableCollection)

Calls the event handler if it was assigned.

procedure TriggerOnItemRenamed(const iOldName: string; const iNewName: string)

Parameters:

  • iOldName: old name
  • iNewName: new name

 

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)