Reset
method (DataWindows)
Description
Clears all the data from a DataWindow control or DataStore
object.
For the syntax to use for deleting graphs within a DataWindow object
that have an external data source, see Reset. For the syntax to use with other
PowerBuilder controls, see the section called “Reset” in PowerScript Reference.
Applies to
|
DataWindow type |
Method applies to |
|---|---|
|
PowerBuilder |
DataWindow control, DataWindowChild object, DataStore |
Syntax
PowerBuilder
|
1 |
integer dwcontrol.Reset ( ) |
|
Argument |
Description |
|---|---|
|
dwcontrol |
A reference to a DataWindow control, DataStore, or |
Return value
Returns 1 if it succeeds and -1 if an error occurs. The return value
is usually not used.
If dwcontrol is null, in PowerBuilder and JavaScript the method
returns null.
Usage
Reset is not the same as deleting rows from the DataWindow object or
child DataWindow. Reset affects the application only, not the database. If
you delete rows and then call the Update method, the rows are deleted from
the database table associated with the DataWindow object. If you call
Reset and then call Update, no changes are made to the table.
PowerBuilder environment
If you call Reset when the Retrieve As Needed option is set, Reset
will clear the rows that have been retrieved. However, because Retrieve
As Needed is on, the DataWindow immediately retrieves the next set of
rows.
To prevent the rows from being retrieved, call DBCancel before
calling Reset. If all the rows have been retrieved (the cursor has been
closed and the RetrieveEnd event has occurred), then when Reset clears
the DataWindow, it stays empty.
Examples
This statement completely clears the contents of dw_employee:
|
1 |
dw_employee.Reset() |
In a DataWindow whose Retrieve As Needed option is on, this example
cancels the retrieval before resetting the DataWindow:
|
1 2 |
dw_employee.DBCancel() dw_employee.Reset() |
See also