Logic Units (Magic xpa 4.x)
The header line represents a logic unit.
Each logic unit entry displays a combo box as the first field, listing the following logic unit types:
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Task Prefix and Suffix – These logic units call the operations that the engine executes, at the beginning or ending of the task. The operations for the Task Prefix logic unit are used for the task’s initialization procedures. The operations for the Task Suffix logic unit are used for the task’s exit procedures; update parameters for a calling task, or print report totals.
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Group Prefix and Suffix – These logic units for Batch task Call operations that the engine executes after the break parameter value has changed. The Group Prefix logic unit is called at the beginning of a group of records for a Batch task when a new value is entered in the break parameter. This logic unit is typically used to print report group header. The Group Suffix logic unit is called when the engine executes operations for a Batch task before processing the record with a break parameter value that has changed. This logic unit is typically used for the printing of report group footers.
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Record Prefix and Suffix – The Record Prefix logic unit executes the operations for every record immediately after the record is read from disk and before interaction starts. The Record Prefix operations are used at the initialization stage of a record, such as the procedural operations that are required before the engine can start processing the record’s parameters. The Record Suffix logic unit executes operations used for updating records that have changed. If the record has not changed, the Record Suffix operations will not be executed. Note that the Batch task is executed every time Magic xpa encounters a Record Suffix logic unit.
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Control Prefix, Verification, Suffix – The Control Prefix logic unit executes the operations required for an insertion point to move into a particular control. Control Prefix operations are used at the initialization stage of a specific control type. A Control logic unit can be called only after a Record logic unit. The Control Verification operations are executed when the engine that is parked in a control, as displayed by the insertion point placement, moves away from the control. These operations are also executed when the control is passed through in Fast mode before the Control Suffix logic unit. The Control Suffix logic unit executes operations used for the control’s exit procedure, that is, just before the engine leaves the control to reset, update, or print a control value.
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Variable – This logic unit lets you select a variable from the Variable list that you want to associate with a specific control type. If you select a variable, the Variable Expression property is disabled. For the specified control, you can place the operations that the engine executes. The Variable handler is for Online tasks only.
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Event – A non-editable field that lets you zoom to the Event Selection dialog box and displays the selected event. When no event is selected the field is blank. For more information, see User-Defined Events.
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Function – Lets you define a user-defined function.
Note: There is no restriction about locating a logic level unit in a specific location according to the level of the logic unit. For example, a Task Suffix logic unit can be created and defined anywhere in the Logic Editor.
Auto Create Task Logic Unit
Magic xpa Engine
