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FILTER EVENT

FILTER EVENT

Does not require any parameters

This command is not thread-safe, it cannot be used in preemptive code.

Description

You call the FILTER EVENT command from within an event-handling project method installed using the ON EVENT CALL command.

If an event-handling method calls FILTER EVENT, the current event is not passed to 4D.

This command removes the current event (i.e., click, keystroke) from the event queue, so 4D will not perform any additional treatment to the one you made in the event-handling project method.

WARNING: Do not create an event-handling method that only calls the FILTER EVENT command, because all the events are going to be ignored by 4D. When you have an event-handling method with only the FILTER EVENT command, type Ctrl+Shift+Backspace (on Windows) or Command-Option-Shift-Control-Backspace (on Macintosh). This converts the On Event Call process into a normal process that does not get any events at all.

Special case: The FILTER EVENT command can also be used within a standard output form method when the form is displayed using the DISPLAY SELECTION or MODIFY SELECTION commands. In this specific case, the FILTER EVENT command allows you to filter double-clicks on the records (and in this way execute actions other than the opening of records in page mode).

To do this, place the following lines in the output form method:

 If(Form event code=On Double Clicked)
    FILTER EVENT
    ... //Process the double-click
 End if

Example

See example for the ON EVENT CALL command.

See also

ON EVENT CALL