DbServer.OrderDescend Method |
Return and optionally change the descending flag of an order.
Namespace: VO
Assembly: VORDDClasses (in VORDDClasses.dll) Version: 2.7
SyntaxVIRTUAL METHOD OrderDescend( uOrder AS USUAL := NIL, oFSIndex AS USUAL := NIL, lNew AS USUAL := NIL ) AS USUAL
Parameters
- uOrder (Optional)
- Type: Usual
The name of the order or a number representing its position in the order list. Using the order name is the preferred method since the position may be difficult to determine using multiple-order index files. If omitted or NIL, the controlling order is assumed. Specifying an invalid value will raise a runtime error. - oFSIndex (Optional)
- Type: Usual
The name of an index file, including an optional drive and directory (no extension should be specified). Use this argument with <cOrder> to remove ambiguity when there are two or more orders with the same name in different index files. If <oFSIndex> is not open by the current process, a runtime error is raised. - lNew (Optional)
- Type: Usual
TRUE dynamically turns on the descending flag for the order, resulting in descending order. FALSE dynamically turns the flag off, resulting in ascending order.
Return Value
Type: UsualIf lNew is not specified, DBServer:OrderDescend() returns the current setting. If <lNewDescend> is specified, the previous setting is returned.
Remarks
DBServer:OrderDescend() changes the ascending/descending flag at runtime only — it does not change the descending flag stored in the actual index file.
 Tip |
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If you are using DbServer:OrderDescend() with Scopes, you need to swap the Top and Bottom scope values !
X# 1oServer:OrderScope (TOPSCOPE, cFrom) 2oServer:OrderScope (BOTTOMSCOPE, cTo) 3oServer:OrderDescend(,, TRUE) 4oServer:OrderScope (TOPSCOPE, cTo) 5oServer:OrderScope (BOTTOMSCOPE, cFrom) |
Examples
The following example illustrates DBServer:OrderDescend(); every order can be both ascending and descending:
X#
1LOCAL oDBCust AS DBServer 2oDBCust := Customer{} 3oDBCust:CreateOrder("Last", "customer", "oDBCust:LastName") 4oDBCust:SetOrderCondition(,,,,,,,,,, TRUE) 5oDBCust:CreateOrder("First", "customer", "oDBCust:FirstName") 6oDBCust:SetOrder("Last") // Last was originally created in ascending order 7oDBCust:OrderDescend(,, TRUE) // Swap it to descending 8// Last will now be processed in descending order 9oDBCust:SetOrder("First") // First was originally created in descending order 10oDBCust:OrderDescend(,, FALSE) // Swap it to ascending 11// First will now be processed in ascending order
See Also