Data.SqlExpr.TCustomSQLDataSet.Active
Delphi
property Active default False;
C++
__property Active = {default=0};
Properties
| Type | Visibility | Source | Unit | Parent |
|---|---|---|---|---|
| property | published | Data.SqlExpr.pas Data.SqlExpr.hpp |
Data.SqlExpr | TCustomSQLDataSet |
Description
Specifies whether or not a dataset is open.
Data.SqlExpr.TCustomSQLDataSet.Active inherits from Data.DB.TDataSet.Active. All content below this line refers to Data.DB.TDataSet.Active.
Specifies whether or not a dataset is open.
Use Active to determine or set whether a dataset is populated with data. When Active is false, the dataset is closed; the dataset cannot read or write data and data-aware controls can not use it to fetch data or post edits. When Active is true, the dataset can be populated with data. It can read data from a database or other source (such as a provider). Depending on the CanModify property, active datasets can post changes.
Setting Active to true:
- Generates a BeforeOpen event.
- Sets the dataset state to dsBrowse.
- Establishes a way to fetch data (typically by opening a cursor).
- Generates an AfterOpen event.
If an error occurs while opening the dataset, dataset state is set to dsInactive, and any cursor is closed.
Setting Active to false:
- Triggers a BeforeClose event.
- Sets the State property to dsInactive.
- Closes the cursor.
- Triggers an AfterClose event.
An application must set Active to false before changing other properties that affect the status of a database or the controls that display data in an application.
Note: Calling the Open method sets Active to true; calling the Close method sets Active to false.
See Also