Docs For Class DataSet

Description

Object
   |
   --Persistent
      |
      --Component
         |
         --DataSet

Located in File: /db.inc.php

This class defines the common methods and properties to work with a collection of data (dataset), no matter how the data is stored.

Child classes might encapsulate access to a simple array in memory, a text file in disk, or even a query on a database.

link: - http://docwiki.embarcadero.com/HTML5_Builder/en/DataSet_Components

Classes extended from DataSet:

SQLClientDataset: This class defines the common methods and properties to work with a collection of data (dataset), no matter how the data is stored.

DBDataSet: Interface that defines properties and methods for a dataset based on database connectivity.

Properties

Summary:

	LimitCount	Number of records from the data provider to be provided by the dataset.
	LimitStart	Number of records from the data provider to be skipped in the dataset, from the start.
	Active	Whether the dataset is open (true) or closed (false). You cannot work on a closed dataset.
	BOF	Whether the current record is the first record of the dataset (true) or not (false).
	CanModify	Whether the dataset can be modified (true) or it is read-only (false).
	EOF	Whether the current record is the last record of the dataset (true) or not (false).
	FieldBuffer	Associative array of key-value pairs describing the content (field-value) of the current record in the underlying storage system.
	FieldCount	Number of fields of the current record.
	Fields	Associative array of key-value pairs describing the content (field-value) of the current record in the dataset.
	Filter	Filter to be applied when retrieving records from the data provider. Only the records matching the conditions defined in the filter will be retrieved and available in the dataset.
	MasterFields	Associative array of key-value pairs, where the 'key' is the name of a field in this dataset, and the 'value' is the name of a field from the MasterSource. This association is used to filter the records retrieved from the data provider into the dataset.
	MasterSource	Instance of DataSet to be used to filter the records that this dataset retrieves from the data provider.
	Modified	Whether the current record has been modified (true) or not (false). For new records, this function returns true when any of its fields has been given a value.
	RecNo	Number that represents the position of the current record in the dataset.
	RecordCount	Total number of records in the dataset.
	State	Current state of the dataset.
Defined in class Component
	Cached	Whether the caching feature should be enabled (true, "1") or not (false, "0").
	Name	Specifies the name for the component. The name is used as an identifier and should be unique.
	Tag	A versatile property of every Component that can be used in any way you want
	ComponentCount	Indicates the number of components owned by the component.
	Components	Lists all the components owned by this component.
	ControlState	A flag indicating the state of the control.
	CSSDescriptor	Returns the CSS descriptor for the component
	DataFieldValue	This property returns the value of the datafield if any.
	NamePath	Specifies the path to uniquely identify a component, qualified by the owner when required.
	Owner	Indicates the component that is responsible for streaming and freeing this component.
Defined in class Persistent
	NamePath	Used to serialize/unserialize. It returns the full path to identify this component.
	Owner	Owner of the component.

property LimitCount (line 525)

string LimitCount

Number of records from the data provider to be provided by the dataset.

For example, if this property is set to "10", the dataset will only contain 10 records from the data provider.

Info

see - DataSet::LimitStart

property LimitStart (line 540)

string LimitStart

Number of records from the data provider to be skipped in the dataset, from the start.

For example, if this property is set to "10", the first record in the dataset will be the 11th record from the data provider.

Info

see - DataSet::LimitCount

property Active (line 381)

bool Active

Whether the dataset is open (true) or closed (false). You cannot work on a closed dataset.

property BOF (line 451)

bool BOF

Whether the current record is the first record of the dataset (true) or not (false).

property CanModify (line 460)

bool CanModify

Whether the dataset can be modified (true) or it is read-only (false).

property EOF (line 471)

bool EOF

Whether the current record is the last record of the dataset (true) or not (false).

property FieldBuffer (line 485)

array FieldBuffer

Associative array of key-value pairs describing the content (field-value) of the current record in the underlying storage system.

Any change to the current record that has not been posted yet will not be reflected in this array.

Info

see - DataSet::Fields

property FieldCount (line 492)

int FieldCount

Number of fields of the current record.

property Fields (line 504)

array Fields

Associative array of key-value pairs describing the content (field-value) of the current record in the dataset.

Any change to the current record will be reflected in this array, even if it has not been posted to the underlying storage system yet.

Info

see - DataSet::FieldBuffer

property Filter (line 511)

void Filter

Filter to be applied when retrieving records from the data provider. Only the records matching the conditions defined in the filter will be retrieved and available in the dataset.

property MasterFields (line 561)

array MasterFields

Associative array of key-value pairs, where the 'key' is the name of a field in this dataset, and the 'value' is the name of a field from the MasterSource. This association is used to filter the records retrieved from the data provider into the dataset.

Suppose you have two datasets, named MasterDataSet and SlaveDataSet, where SlaveDataSet (this dataset) has MasterDataSet associated to its MasterSource property (MasterSource = $MasterDataSet), and SlaveDataSet's MasterFields property is defined as array('category_id' => 'id').

As a result of the configuration above, SlaveDataSet would only contain records whose 'category_id' field has the same value as the 'id' field of the current record of the MasterDataSet.

Info

see - DataSet::MasterSource

property MasterSource (line 575)

DataSet MasterSource

Instance of DataSet to be used to filter the records that this dataset retrieves from the data provider.

This property must be used in combination with MasterFields, else it is useless.

Info

see - DataSet::MasterFields

property Modified (line 588)

bool Modified

Whether the current record has been modified (true) or not (false). For new records, this function returns true when any of its fields has been given a value.

property RecNo (line 600)

int RecNo

Number that represents the position of the current record in the dataset.

Change this property to navigate to a record in a different position.

property RecordCount (line 621)

int RecordCount

Total number of records in the dataset.

property State (line 634)

int State

Current state of the dataset.

'dsInactive' indicates the dataset is closed. 'dsBrowse' is the standard state when the dataset is open. 'dsEdit' indicates that a record of the dataset is being modified. 'dsInsert' indicates that a new record, to be added to the dataset, is being defined.

property Cached

Whether the caching feature should be enabled (true, "1") or not (false, "0").

This property is implemented in Component::Cached

property Name

Specifies the name for the component. The name is used as an identifier and should be unique.

This property is implemented in Component::Name

property Tag

A versatile property of every Component that can be used in any way you want

This property is implemented in Component::Tag

property ComponentCount

Indicates the number of components owned by the component.

This property is implemented in Component::ComponentCount

property Components

Lists all the components owned by this component.

This property is implemented in Component::Components

property ControlState

A flag indicating the state of the control.

This property is implemented in Component::ControlState

property CSSDescriptor

Returns the CSS descriptor for the component

This property is implemented in Component::CSSDescriptor

property DataFieldValue

This property returns the value of the datafield if any.

This property is implemented in Component::DataFieldValue

property NamePath

Specifies the path to uniquely identify a component, qualified by the owner when required.

This property is implemented in Component::NamePath

property Owner

Indicates the component that is responsible for streaming and freeing this component.

This property is implemented in Component::Owner

property NamePath

Used to serialize/unserialize. It returns the full path to identify this component.

This property is implemented in Persistent::NamePath

property Owner

Owner of the component.

This property is implemented in Persistent::Owner

Methods

Summary:

	append	Begins an append operation for the current record.
	beginInsertAppend	Prepares the dataset to enter insert/append mode.
	cancel	Stops the current operation to modify the dataset without applying any change, effectively rejecting those changes.
	checkActive	Raises an exception if the dataset is not open.
	checkBidirectional	Raises an exception if the dataset is not bidirectional, but unidirectional.
	checkBrowseMode	If the dataset is open and the dataset is in append/edit/insert mode, it posts any unsaved changes to the data provider, and takes the dataset back into browse mode.
	checkCanModify	Raises an exception if the dataset is read-only.
	checkOperation	Calls the given $method that performs an operation on the DataSet.
	checkStateToModify	Raises an exception if the dataset is not in append/edit/insert mode.
	clearBuffers	Empties the buffer for the current record.
	close	Closes the dataset. The dataset will be emptied of records, and you won't be able to work with the dataset until you open it again.
	delete	Removes the current record from the dataset.
	edit	Begins an edit operation for the current record.
	endInsertAppend	Performs some steps that are needed after setting the dataset to either the append or the insert modes.
	first	Points the record cursor to the first record in the dataset.
	freeFieldBuffers	Empties the buffer for the current record.
	initRecord	Empties (sets to NULL) the value of any field in the current record.
	insert	Begins an insert operation for the current record.
	internalCancel	Cancels the posting to the data provider of the changes made to the dataset.
	internalClose	Empties the dataset from any data.
	internalDelete	Deletes the current record from the data provider.
	internalEdit	Takes the dataset into edit mode.
	internalFirst	Points the record cursor to the first record in the data provider.
	internalInsert	Takes the dataset into insert/append mode.
	internalLast	Points the record cursor to the last record in the data provider.
	internalMoveBy	Moves the record cursor the given number of positions in the data provider. Negative values move the cursor backwards.
	internalOpen	Fills the dataset with the records from its data provider.
	internalPost	Posts to the data provider the changes made to the dataset.
	isUnidirectional	Returns true if the dataset is unidirectional, false otherwise.
	last	Points the record cursor to the last record in the dataset.
	loaded	Initializes the component after the form file has been read into memory. [Overrides Component::loaded()]
	moveBy	Moves the record cursor the given number of positions. Use negative values to move the cursor backwards.
	next	Points the record cursor to the next record in the dataset.
	NextRecord	Points the record cursor to the next record.
	open	Opens the dataset. When a dataset is opened, it gets filled with the records from its data provider.
	post	Stops the current operation to modify the dataset, and performs the actual changes.
	prior	Points the record cursor to the previous record in the dataset.
	PriorRecord	Points the record cursor to the previous record.
	refresh	Reloads the dataset with the records from the data provider.
	serialize	Stores this object into the session. [Overrides Persistent::serialize()]
	unserialize	This method uses PHP reflection to iterate through published properties (those for which there is a getter method) and retrieve those stored by a previous call to serialize(). [Overrides Persistent::unserialize()]
	updateFieldBuffer	Updates the field buffer, the buffer containing the unsaved changes to the current record.
Defined in class Component
	__construct	Component constructor.
	ajaxCall	Dumps the JavaScript code to make an AJAX call to the server-side version of the script.
	beginCache	Start caching from here.
	bindjQueryEvent	Returns the javascript code to bind a js event with JQuery
	bindJSEvent	Returns the javascript code to bind a js event
	callEvent	Calls a server event.
	dumpAdditionalCSS	Dumps additional CSS code required by the component.
	dumpChildrenFormItems	This method is called by the page just after dumping the starting form tag.
	dumpChildrenHeaderCode	Dumps the header code for all the children
	dumpChildrenJavascript	Dumps the JavaScript code for all the children components.
	dumpContents	Renders the control.
	dumpCSS	Dumps CSS code required by the component.
	dumpFormItems	Dumps code just after the form tag, useful to dump hidden fields for state retrieving for non visible components
	dumpHeaderCode	Dumps code in the header of the final webpage required by the component.
	dumpHiddenKeyFields	Dumps hidden field values for the key record
	dumpJavascript	Dumps JavaScript code required by the component.
	dumpJSEvent	Dumps javascript code for an event
	endCache	Stop caching at this point.
	fixupProperty	Resolves the right reference to an object property
	generateAjaxEvent	Returns the javascript code to generate an ajax call.
	hasValidDataField	Returns true if a valid data field is attached to the component
	init	Initializes a component
	insertComponent	Inserts a component into the component's collection
	loaded	Initializes the component after the form file has been read into memory.
	loadedChildren	Iterates through any component in the page, and calls its loaded() method.
	loadResource	Loads this component from a string.
	pagecreate	Prints client-side code that should be executed once the DOM is loaded on the user agent.
	preinit	Method called before init().
	removeComponent	Removes a component from the component's collection
	serializeChildren	Serializes all children
	show	Dumps the code for the control to the output.
	showCSS	Dumps the CSS for the component, qualifying it by the owner name, so you can mix pages in the same page
	unserializeChildren	Unserializes all children by calling unserialize for all the components
	updateDataField	Updates the field on the dataset attached, if any
Defined in class Persistent
	allowserialize	This method provides an opportunity for the component developer to prevent the serialization/unserialization of a property.
	assign	Assigns the source properties to this object.
	assignError	Raises an assignment error.
	assignTo	Assigns this object to another object.
	handleUndefinedProperty	Performs the error reporting for undefined properties.
	inSession	This method determines if this object exists in the current session.
	serialize	Stores this object into the session.
	unserialize	This method uses PHP reflection to iterate through published properties (those for which there is a getter method) and retrieve those stored by a previous call to serialize().
Defined in class Object
	__construct	Constructs an object and initializes its data before the object is first used.
	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.
	inheritsFrom	Determines the relationship of two object types.
	methodExists	Check if a method exists declared on this object instance.
	__get	To virtualize properties
	__set	To virtualize properties

Method append (line 780)

void append( )

Begins an append operation for the current record.

In an append operation, you define a brand new record, and then you add it to the dataset.

For example, imagine you have a dataset with the fields Name and Surname. This is how you would add a new record to it:

$dataSet->append();
$dataSet->Name = 'Jane';
$dataSet->Surname = 'Doe';
$dataSet->post();

Now the dataset would have a new record for Jane Doe.

Any unsaved changes to the current record will be saved to the dataset upon calling this method. Imagine the following code was used instead of the four statements above:

$dataSet->append();
$dataSet->Name = 'John';
$dataSet->Surname = 'Doe';
$dataSet->append();
$dataSet->Name = 'Jane';
$dataSet->Surname = 'Doe';
$dataSet->post();

Then the dataset would have two new records, one for John Doe and another one for Jane Doe.

You can use this feature to append records to the dataset in a loop like this:

$names = array('John' => 'Doe', 'Jane' => 'Doe');
foreach ($names as $name => $surname)
{
$dataSet->append();
$dataSet->Name = $name;
$dataSet->Surname = $surname;
}
$dataSet->post();

Info

see - DataSet::cancel, DataSet::insert, DataSet::post

Method beginInsertAppend (line 1516)

void beginInsertAppend( )

Prepares the dataset to enter insert/append mode.

Method cancel (line 1100)

void cancel( )

Stops the current operation to modify the dataset without applying any change, effectively rejecting those changes.

$dataSet->edit();
$dataSet->Name = 'John';
$dataSet->cancel(); // The name of the current record is not changed to 'John'.

Info

see - DataSet::append, DataSet::edit, DataSet::insert

Method checkActive (line 1442)

void checkActive( )

Raises an exception if the dataset is not open.

Info

throws - EDatabaseError

Method checkBidirectional (line 1415)

void checkBidirectional( )

Raises an exception if the dataset is not bidirectional, but unidirectional.

Info

throws - EDatabaseError

Method checkBrowseMode (line 1490)

void checkBrowseMode( )

If the dataset is open and the dataset is in append/edit/insert mode, it posts any unsaved changes to the data provider, and takes the dataset back into browse mode.

If the dataset is closed, it raises an exception.

Info

throws - EDatabaseError

Method checkCanModify (line 1457)

void checkCanModify( )

Raises an exception if the dataset is read-only.

Info

throws - EDatabaseError

Method checkOperation (line 1126)

void checkOperation( string $method, string $event)

Calls the given $method that performs an operation on the DataSet.

Parameters

string $method: Name of the method to be called (e.g. "internalPost").
string $event: Name of the event to be triggered in case of error (e.g. "onerror").

Method checkStateToModify (line 1472)

void checkStateToModify( )

Raises an exception if the dataset is not in append/edit/insert mode.

Info

throws - EDatabaseError

Method clearBuffers (line 1551)

void clearBuffers( )

Empties the buffer for the current record.

Method close (line 676)

void close( )

Closes the dataset. The dataset will be emptied of records, and you won't be able to work with the dataset until you open it again.

Info

see - DataSet::open

Method delete (line 792)

void delete( )

Removes the current record from the dataset.

Method edit (line 854)

void edit( )

Begins an edit operation for the current record.

In an edit operation, you modify the data in the current record, and then update the dataset with those changes.

For example, imagine you have a dataset with the fields Name and Surname, and for those fields, the current record has the values 'Jane' and 'Doe' respectively. You could use this method to change the Name of the record:

$dataSet->edit();
$dataSet->Name = 'John';
$dataSet->post();

Now the dataset record for Jane Doe would be replaced by a record for John Doe.

Any unsaved changes to the current record will be saved to the dataset upon calling this method.

$dataSet->append();
$dataSet->Name = 'John';
$dataSet->Surname = 'Doe';
$dataSet->edit(); // The append operation stops and the new record, for John Doe, is added to the dataset.
$dataSet->Name = 'Jane';
$dataSet->post(); // The Name of the record, which was already in the dataset, is changed to 'Jane'.

Info

see - DataSet::cancel, DataSet::insert, DataSet::post

Method endInsertAppend (line 1529)

void endInsertAppend( )

Performs some steps that are needed after setting the dataset to either the append or the insert modes.

Method first (line 883)

void first( )

Points the record cursor to the first record in the dataset.

Any unsaved changes to the current record will be saved to the dataset upon calling this method.

$dataSet->edit();
$dataSet->Name = 'Jane';
$dataSet->first();

When you call first(), the Name of the current record is changed to 'Jane' in the dataset, and then the record cursor is moved to the first record.

Method freeFieldBuffers (line 1580)

void freeFieldBuffers( )

Empties the buffer for the current record.

Method initRecord (line 1563)

void initRecord( )

Empties (sets to NULL) the value of any field in the current record.

Method insert (line 726)

void insert( )

Begins an insert operation for the current record.

In an insert operation, you define a new record by modifying the data in the current record, and then you add that new record to the dataset.

$dataSet->insert();
$dataSet->Name = 'John';
$dataSet->post();

Now the dataset would have both a record for Jane Doe and a record for John Doe.

Any unsaved changes to the current record will be saved to the dataset upon calling this method. Imagine the following code was used instead of the three statements above:

$dataSet->insert();
$dataSet->Name = 'John';
$dataSet->insert();
$dataSet->Name = 'Jack';
$dataSet->post();

Then the dataset would have records for Jane Doe, John Doe and Jack Doe.

You can use this feature to insert records with values in common to the current record using a loop like this:

$names = array('John', 'Jake', 'Jennifer', 'James', 'Judy');
foreach ($names as $name)
{
$dataSet->insert();
$dataSet->Name = $name;
}
$dataSet->post();

Info

see - DataSet::append, DataSet::cancel, DataSet::edit, DataSet::post

Method internalCancel (line 1373)

void internalCancel( )

Cancels the posting to the data provider of the changes made to the dataset.

Info

see - DataSet::cancel

Method internalClose (line 1298)

void internalClose( )

Empties the dataset from any data.

Info

see - DataSet::internalOpen, DataSet::close

Method internalDelete (line 1325)

void internalDelete( )

Deletes the current record from the data provider.

Info

see - DataSet::delete

Method internalEdit (line 1316)

void internalEdit( )

Takes the dataset into edit mode.

Info

see - DataSet::edit

Method internalFirst (line 1334)

void internalFirst( )

Points the record cursor to the first record in the data provider.

Info

see - DataSet::first

Method internalInsert (line 1307)

void internalInsert( )

Takes the dataset into insert/append mode.

Info

see - DataSet::insert, DataSet::append

Method internalLast (line 1343)

void internalLast( )

Points the record cursor to the last record in the data provider.

Info

see - DataSet::last

Method internalMoveBy (line 1355)

void internalMoveBy( int $positions)

Moves the record cursor the given number of positions in the data provider. Negative values move the cursor backwards.

Parameters

int $positions:

Info

see - DataSet::moveBy

Method internalOpen (line 1289)

void internalOpen( )

Fills the dataset with the records from its data provider.

Info

see - DataSet::internalClose, DataSet::open

Method internalPost (line 1364)

void internalPost( )

Posts to the data provider the changes made to the dataset.

Info

see - DataSet::post

Method isUnidirectional (line 1430)

bool isUnidirectional( )

Returns true if the dataset is unidirectional, false otherwise.

Method last (line 922)

void last( )

Points the record cursor to the last record in the dataset.

Any unsaved changes to the current record will be saved to the dataset upon calling this method.

$dataSet->edit();
$dataSet->Name = 'Jane';
$dataSet->last();

When you call last(), the Name of the current record is changed to 'Jane' in the dataset, and then the record cursor is moved to the last record.

Method loaded (line 336)

void loaded( )

Overrides : Component::loaded() Initializes the component after the form file has been read into memory.

Method moveBy (line 1019)

void moveBy( int $positions)

Moves the record cursor the given number of positions. Use negative values to move the cursor backwards.

For example, if the current record of the dataset is the 6th:

$dataSet->moveBy(2); // The 8th is now the current record.
$dataSet->moveBy(-5); // The 3rd is now the current record (8 - 5 = 3).

The movement goes as far as it can. If you provide a number that would take the cursor to a position outside of the range of records, the cursor will be moved just until the limit (the first or the last record).

For example, if you are in the 10th of the 30 records the dataset has:

$dataSet->moveBy(-21); // Takes you to the first record.
$dataSet->moveBy(54); // Takes you to the last record.

Any unsaved changes to the current record will be saved to the dataset upon calling this method.

$dataSet->edit();
$dataSet->Name = 'Jane';
$dataSet->moveBy(6);

When you call moveBy(), the Name of the current record is changed to 'Jane' in the dataset, and then the record cursor is moved the given positions.

Parameters

int $positions:

Method next (line 953)

void next( )

Points the record cursor to the next record in the dataset.

Any unsaved changes to the current record will be saved to the dataset upon calling this method.

$dataSet->edit();
$dataSet->Name = 'Jane';
$dataSet->next();

When you call next(), the Name of the current record is changed to 'Jane' in the dataset, and then the record cursor is moved to the next record.

Method NextRecord (line 1390)

bool NextRecord( )

Points the record cursor to the next record.

Info

return - Returns false on EOF, true otherwise.

Method open (line 665)

void open( )

Opens the dataset. When a dataset is opened, it gets filled with the records from its data provider.

Info

see - DataSet::close

Method post (line 1070)

void post( )

Stops the current operation to modify the dataset, and performs the actual changes.

$dataSet->edit();
$dataSet->Name = 'John';
$dataSet->post(); // It is at this point where the Name is actually changed in the dataset.

Info

see - DataSet::append, DataSet::edit, DataSet::insert

Method prior (line 972)

void prior( )

Points the record cursor to the previous record in the dataset.

Any unsaved changes to the current record will be saved to the dataset upon calling this method.

$dataSet->edit();
$dataSet->Name = 'Jane';
$dataSet->prior();

When you call prior(), the Name of the current record is changed to 'Jane' in the dataset, and then the record cursor is moved to the previous record.

Method PriorRecord (line 1400)

bool PriorRecord( )

Points the record cursor to the previous record.

Info

return - Returns false on BOF, true otherwise.

Method refresh (line 980)

void refresh( )

Reloads the dataset with the records from the data provider.

Method serialize (line 344)

void serialize( )

Overrides : Persistent::serialize() Stores this object into the session.

Method unserialize (line 358)

void unserialize( )

Overrides : Persistent::unserialize() This method uses PHP reflection to iterate through published properties (those for which there is a getter method) and retrieve those stored by a previous call to serialize().

Method updateFieldBuffer (line 1383)

void updateFieldBuffer( )

Updates the field buffer, the buffer containing the unsaved changes to the current record.

This method is called whenever the record cursor is moved to a different record, so the unsaved changes to the previously pointed record are ignored and replaced by those of the currently pointed record.

Events

Summary:

	OnAfterCancel	Triggered once the unsaved changes to the current record have been successfully reverted.
	OnAfterClose	Triggered right after the dataset has been closed.
	OnAfterDelete	Triggered after a successful deletion of what was the current record.
	OnAfterEdit	Triggered after an edit operation has started.
	OnAfterInsert	Triggered after an insert or append operation has started.
	OnAfterOpen	Triggered right after the dataset has been opened.
	OnAfterPost	Triggered once the unsaved changes to the current record have been successfully saved to the dataset.
	OnBeforeCancel	Triggered when the unsaved changes to the current record are about to be reverted.
	OnBeforeClose	Triggered right before the dataset has been closed.
	OnBeforeDelete	Triggered when the current record is about to be deleted.
	OnBeforeEdit	Triggered when an edit operation is about to start.
	OnBeforeInsert	Triggered when an insert or append operation is about to start.
	OnBeforeOpen	Triggered right before the dataset is opened.
	OnBeforePost	Triggered when the unsaved changes to the current record are about to be saved to the dataset.
	OnDeleteError	Triggered whenever an error occurs while deleting the current record.
	OnNewRecord	Triggered once a new record has been added to the dataset (not to the underlying database).
	OnPostError	Triggered whenever an error occurs while saving to the dataset the unsaved changes to the current record.
Defined in class Component
	OnAfterShow	Fires the Event after showing the control.
	OnBeforeShow	Fires the Event before showing the control.
	OnShow	Fires the Event at the same moment the control is shown. Some controls can prevent the control from being shown when this event is attached.

property OnAfterCancel (line 1243)

void OnAfterCancel

Triggered once the unsaved changes to the current record have been successfully reverted.

property OnAfterClose (line 1179)

void OnAfterClose

Triggered right after the dataset has been closed.

property OnAfterDelete (line 1227)

void OnAfterDelete

Triggered after a successful deletion of what was the current record.

property OnAfterEdit (line 1211)

void OnAfterEdit

Triggered after an edit operation has started.

property OnAfterInsert (line 1195)

void OnAfterInsert

Triggered after an insert or append operation has started.

property OnAfterOpen (line 1163)

void OnAfterOpen

Triggered right after the dataset has been opened.

property OnAfterPost (line 1259)

void OnAfterPost

Triggered once the unsaved changes to the current record have been successfully saved to the dataset.

property OnBeforeCancel (line 1235)

void OnBeforeCancel

Triggered when the unsaved changes to the current record are about to be reverted.

property OnBeforeClose (line 1171)

void OnBeforeClose

Triggered right before the dataset has been closed.

property OnBeforeDelete (line 1219)

void OnBeforeDelete

Triggered when the current record is about to be deleted.

property OnBeforeEdit (line 1203)

void OnBeforeEdit

Triggered when an edit operation is about to start.

property OnBeforeInsert (line 1187)

void OnBeforeInsert

Triggered when an insert or append operation is about to start.

property OnBeforeOpen (line 1155)

void OnBeforeOpen

Triggered right before the dataset is opened.

property OnBeforePost (line 1251)

void OnBeforePost

Triggered when the unsaved changes to the current record are about to be saved to the dataset.

property OnDeleteError (line 1267)

void OnDeleteError

Triggered whenever an error occurs while deleting the current record.

property OnNewRecord (line 653)

void OnNewRecord

Triggered once a new record has been added to the dataset (not to the underlying database).

The new record might have been added by starting either an append or an insert operation.

You may use this event to make some changes to the new record that will not count as a modification, so the record won't be commited to the underlying database unless it is further modified later, or you call completeTrans().

Info

see - DataSet::append, DataSet::insert

property OnPostError (line 1275)

void OnPostError

Triggered whenever an error occurs while saving to the dataset the unsaved changes to the current record.

property OnAfterShow

Fires the Event after showing the control.

This event is implemented in Component::OnAfterShow

property OnBeforeShow

Fires the Event before showing the control.

This event is implemented in Component::OnBeforeShow

property OnShow

Fires the Event at the same moment the control is shown. Some controls can prevent the control from being shown when this event is attached.

This event is implemented in Component::OnShow

Javascript Events

Summary:

[none]

Class DataSet

Description

This class defines the common methods and properties to work with a collection of data (dataset), no matter how the data is stored.

Properties

Defined in class Component

Defined in class Persistent

property LimitCount (line 525)

string LimitCount

Number of records from the data provider to be provided by the dataset.

Info

property LimitStart (line 540)

string LimitStart

Number of records from the data provider to be skipped in the dataset, from the start.

Info

property Active (line 381)

bool Active

Whether the dataset is open (true) or closed (false). You cannot work on a closed dataset.

property BOF (line 451)

bool BOF

Whether the current record is the first record of the dataset (true) or not (false).

property CanModify (line 460)

bool CanModify

Whether the dataset can be modified (true) or it is read-only (false).

property EOF (line 471)

bool EOF

Whether the current record is the last record of the dataset (true) or not (false).

property FieldBuffer (line 485)

array FieldBuffer

Associative array of key-value pairs describing the content (field-value) of the current record in the underlying storage system.

Info

property FieldCount (line 492)

int FieldCount

Number of fields of the current record.

property Fields (line 504)

array Fields

Associative array of key-value pairs describing the content (field-value) of the current record in the dataset.

Info

property Filter (line 511)

void Filter

Filter to be applied when retrieving records from the data provider. Only the records matching the conditions defined in the filter will be retrieved and available in the dataset.

property MasterFields (line 561)

array MasterFields

Associative array of key-value pairs, where the 'key' is the name of a field in this dataset, and the 'value' is the name of a field from the MasterSource. This association is used to filter the records retrieved from the data provider into the dataset.

Info

property MasterSource (line 575)

DataSet MasterSource

Instance of DataSet to be used to filter the records that this dataset retrieves from the data provider.

Info

property Modified (line 588)

bool Modified

Whether the current record has been modified (true) or not (false). For new records, this function returns true when any of its fields has been given a value.

property RecNo (line 600)

int RecNo

Number that represents the position of the current record in the dataset.

property RecordCount (line 621)

int RecordCount

Total number of records in the dataset.

property State (line 634)

int State

Current state of the dataset.

property Cached

Whether the caching feature should be enabled (true, "1") or not (false, "0").

property Name

Specifies the name for the component. The name is used as an identifier and should be unique.

property Tag

A versatile property of every Component that can be used in any way you want

property ComponentCount

Indicates the number of components owned by the component.

property Components

Lists all the components owned by this component.

property ControlState

A flag indicating the state of the control.

property CSSDescriptor

Returns the CSS descriptor for the component

property DataFieldValue

This property returns the value of the datafield if any.

property NamePath

Specifies the path to uniquely identify a component, qualified by the owner when required.

property Owner

Indicates the component that is responsible for streaming and freeing this component.