TWebClientDataSet

Description

TWebClientDataSet is the class for an in browser memory dataset. Client datasets can work with data retrieved from a REST request or by directly assigning JSON arrays. They cache that data in memory, maintain a record of any changes in a change log, and apply cached updates at a later point back to the source of the data.

Properties for TWebClientDataSet

Property	Description
Active	Specifies whether or not a dataset is open
Connection	Sets the TWebClientConnection component that can take care of performing the REST requests to load the data in the TWebClientDataSet
DataSource	Represents the data source of another dataset that supplies values to the dataset
Fields	Use Fields to access field components. If fields are generated dynamically at runtime, the order of field components in Fields corresponds directly to the order of columns in the table or tables underlying a dataset. If a dataset uses persistent fields, then the order of field components corresponds to the ordering of fields specified in the Fields editor at design time
FieldDefs	Points to the list of field definitions for the dataset
Params	Use Params to specify parameter values that the provider should pass to a source dataset
RecNo	Indicates the active record in the dataset
RecordCount	Returns the number of records in the dataset
Rows: TJSArray	JSON array property allow to set the dataset data from a JSON array

Methods for TWebClientDataSet

Method	Description
Append	Sets the dataset in insert mode by appending a new record to it
AppendAsync: TJSPromise	Promise based version of Append
ApplyUpdates	Sends all updated, inserted, and deleted records from the client dataset to the provider for writing to the database
ApplyUpdatesAsync: TJSPromise	Promise based version of ApplyUpdates
Cancel	Cancels unposted changes to the current record
ClearFields	Removes all fields from the fields collection
Close	Closes the dataset. Equivalent to setting Active = false
Delete	Deletes the active record and positions the dataset on the next record
Edit	Sets the dataset in edit mode
EmptyDataSet	Removes all data (records) from the dataset
First	Moves to the first record in the dataset
Insert	Puts the dataset in insert state
InsertAsync: TJSPromise	Promise based version of Insert
Last	Moves to the last record in the dataset
Next	Moves to the next record in the dataset
Open	Opens the dataset. Equivalent to setting Active = true
OpenAsync: TJSPromise	Promise based version of Open
Post	Writes a modified record to the Data property or the change log
PostAsync: TJSPromise	Promise based version of Post
Prior	Moves to the previous record in the dataset

Events for TWebClientDataSet

Event	Description
AfterCancel	Event triggered after a cancel operation on the dataset
AfterClose	Event triggered after a dataset close
AfterDelete	Event triggered after a delete operation on the dataset
AfterEdit	Event triggered after the dataset was set in edit mode
AfterInsert	Event triggered after the dataset was set in insert mode
AfterOpen	Event triggered after a dataset open
AfterPost	Event triggered after a post operation on the dataset
AfterScroll	Event triggered after a scroll
BeforeCancel	Event triggered just before a cancel operation will be performed on the dataset
BeforeClose	Event triggered just before the dataset will be effectively closed
BeforeDelete	Event triggered just before a delete operation will be performed on the dataset
BeforeEdit	Event triggered just before the dataset is set into edit mode
BeforeInsert	Event triggered just before an insert operation will be performed on the dataset
BeforeOpen	Event triggered just before the dataset will be effectively opened
BeforePost	Event triggered just before a post operation will be performed on the dataset
BeforeScroll	Event triggered just before a scroll will happen in the dataset
OnCalcFields	Occurs when an application recalculates calculated fields.
OnDeleteError	Occurs when an application attempts to delete a record and an exception is raised.
OnEditError	Occurs when an application attempts to modify or insert a record and an exception is raised.
OnFilterRecord	Occurs each time a different record in the dataset becomes the active record and filtering is enabled.
OnNewRecord	Occurs when an application inserts or appends a new dataset record.
OnPostError	Occurs when an application attempts to modify or insert a record and an exception is raised.
OnUpdateRecord	Occurs when cached updates are applied to a record.