TSLDataSet Class Reference

Detailed Description

Entity specific DataSet access methods.

Allows access to the Data held by an individual TSLEntity.

Public Member Functions
bool	addData (const TSLVariant *values, int count)
bool	addData (const TSLVariant &value)
void	copy (const TSLDataSet *source)
TSLDataHandler *	dataHandler () const
const char *	findKey (const char *field_name) const
const char *	findName (const char *field_key) const
bool	getAvailableField (int index, TSLSimpleString &field) const
bool	getAvailableKey (int index, TSLSimpleString &key) const
const TSLVariant *	getData (int position, bool search_external=false) const
const TSLVariant *	getData (const char *id, int nth_copy=0, bool search_external=false) const
bool	readOnly () const
int	numAvailableFields () const
int	numAvailableKeys () const
bool	removeData (int position)
bool	removeData (const char *id, int nth_copy=0)
int	sizeData (bool search_external=false) const
int	sizeData (const char *id, bool search_external=false) const
bool	updateData (const TSLVariant &value, int position)
bool	updateData (const TSLVariant &value, const char *id, int nth_copy=0)

Member Function Documentation

addData() [1/2]

bool TSLDataSet::addData

(

const TSLVariant &

value

)

Handles the addition of a single variants to the TSLDataSet. Addition is not allowed if the TSLDataSet is read only as in the case of TSLDataSet for TSLEntities retrieved from a TSLMapDataLayer.

Parameters

value

reference to a single TSLVariant object to be added.

Returns

True if data is successfully added, false otherwise.

addData() [2/2]

bool TSLDataSet::addData	(	const TSLVariant *	values,
		int	count )

Handles the addition of a set of variants to the TSLDataSet. Addition is not allowed if the TSLDataSet is read only as in the case of TSLDataSet for TSLEntities retrieved from a TSLMapDataLayer.

Parameters

values	pointer to the first of a set of TSLVariants
count	number of TSLVariants being passed in pass

Returns

True if successfully added, false otherwise.

copy()

void TSLDataSet::copy

(

const TSLDataSet *

source

)

Copies the contents of the given TSLDataSet into this TSLDataSet. This operation erases any existing data within this dataset.

The TSLDataHandler associated with this dataset (if any) is unaffected by this operation.

Parameters

source

The TSLDataSet to copy the contents of.

dataHandler()

TSLDataHandler * TSLDataSet::dataHandler

(

)

const

Returns a pointer to the data handler for this dataset.

The data handler can be used to determine the name, and optionally the type and length, for a given field key.

Returns

a pointer to the data handler.

findKey()

const char * TSLDataSet::findKey

(

const char *

field_name

)

const

Gets the two character field key which identifies a data attribute associated with the specified human readable field name for an entity of the feature type which owns the TSLDataSet.

Parameters

field_name

human readable field name.

Returns

The two character code associated with the human readable name. If the field name is not understood by the handler then the method will return 0.

findName()

const char * TSLDataSet::findName

(

const char *

field_key

)

const

Gets the human readable field name which identifies a data attribute associated with the specified 2 character field_key for an entity of the feature type which owns the TSLDataSet.

Parameters

field_key

The two character identifier for which data attribute to recover.

Returns

human readable field name.

getAvailableField()

bool TSLDataSet::getAvailableField	(	int	index,
		TSLSimpleString &	field ) const

Gets the indexed field name

Parameters

index	index to the field name to retrieve. This should be less than the return value for numAvailableFields.
field	This will be populated with the field found at the passed index, should one exist.

Returns

true if and entry is found, false otherwise,

getAvailableKey()

bool TSLDataSet::getAvailableKey	(	int	index,
		TSLSimpleString &	key ) const

Gets the indexed key name.

Parameters

index	index to the key name to retrieve. This should be less than the return value for numAvailableKeys.
key	This will be populated with the key found at the passed index, should one exist.

Returns

true if and entry is found, false otherwise,

getData() [1/2]

const TSLVariant * TSLDataSet::getData	(	const char *	id,
		int	nth_copy = 0,
		bool	search_external = false ) const

Gets the nth_copy of a data attribute identified by id. If search external is set it will also search any external data sources if available.

Parameters

id	Identifier for the data element to be retrieved. This may be the two character code of the TSLVariant to retrieve or the human readable version of the code.
nth_copy	The count of the data identified by "id" to be retrieved. If no position is given the first occurrence is to be retrieved. Otherwise the valid range of inputs is from 1 (the first item) to the value returned by sizeData( id ) (the last item).
search_external	Indicates if any external data sources should be searched. If no value is given no external search will be undertaken.

Returns

a pointer to a TSLVariant with the given id at the requested position, or 0 if no valid data attribute was found.

getData() [2/2]

const TSLVariant * TSLDataSet::getData	(	int	position,
		bool	search_external = false ) const

Gets the data attribute at the position specified. If search external is set it will also search any external data sources if available.

Parameters

position	The position of the data attribute to retrieve.
search_external	Indicates if any external data sources should be searched. If no value is given no external search will be undertaken.

Returns

a pointer to a TSLVariant at the given position, or 0 if no valid data attribute was found.

numAvailableFields()

int TSLDataSet::numAvailableFields

(

)

const

Counts the available human readable field names for this dataset

Returns

number of fields if any were found, 0 otherwise.

numAvailableKeys()

int TSLDataSet::numAvailableKeys

(

)

const

Count of the available keys understood by this TSLDataSet

Returns

number of keys if any were found, 0 otherwise.

readOnly()

bool TSLDataSet::readOnly

(

)

const

Indicates if the TSLDataSet is read only.

Returns

True if the TSLDataSet is read only, false otherwise.

removeData() [1/2]

bool TSLDataSet::removeData	(	const char *	id,
		int	nth_copy = 0 )

Removes nth_copy of the data attribute identified by the given id. Removal is not allowed if the TSLDataSet is read only as in the case of TSLDataSet for TSLEntities retrieved from a TSLMapDataLayer.

Parameters

id	Identifier for the data element to be removed.
nth_copy	The index of the data attribute with the given id that is to be removed.

Returns

True if the data attribute was found and removed, false otherwise.

removeData() [2/2]

bool TSLDataSet::removeData

(

int

position

)

Removes data at the given position.

Removal is not allowed if the TSLDataSet is read only as in the case of TSLDataSet for TSLEntities retrieved from a TSLMapDataLayer.

Parameters

position

the position of the data attribute to remove

Returns

True if the data attribute was successfully removed, false otherwise.

sizeData() [1/2]

int TSLDataSet::sizeData

(

bool

search_external = false

)

const

Counts the number of available items in the TSLDataSet

Parameters

search_external

indicates if any external data sources should be searched when calculating the count.

Returns

the number of data attributes stored.

sizeData() [2/2]

int TSLDataSet::sizeData	(	const char *	id,
		bool	search_external = false ) const

Counts the number of available items with the given id.

Parameters

id	the id of the attribute to get
search_external	indicates if any external data sources should be searched when calculating the count.

Returns

the number of data items stored.

updateData() [1/2]

bool TSLDataSet::updateData	(	const TSLVariant &	value,
		const char *	id,
		int	nth_copy = 0 )

Updates the nth copy of the specific variant id.

Not allowed if the TSLDataSet is read only.

This will not allow changes to any of the MapLink specific attributes or to any external data items. Note that this does not change the 'key' or 'id', merely update the value.

Parameters

value	reference to the TSLVariant object that is to update the TSLDataSet
id	Identifier for the data element to be updated. This may be the two character code of the TSLVariant to retrieve or the human readable version of the code.
nth_copy	The count of the data identified by "id" to be retrieved. If no position is given the first occurrence is to be updated.

Returns

True if the data was successfully updated. False otherwise.

updateData() [2/2]

bool TSLDataSet::updateData	(	const TSLVariant &	value,
		int	position )

Updates the variant at the specified position for the entity.

Not allowed if the TSLDataSet is read only.

This will not allow changes to any of the MapLink specific attributes or to any external data items. Note that this method replaces the variant totally, not just updating the value. This means that the 'id' or 'key' could change.

Parameters

value	reference to the TSLVariant object that is to update the TSLDataSet
position	the position of the data attribute in the TSLDataSet to update.

Returns

True if the data was successfully updated. False otherwise.