KeyToOrder (return ORDER expression for a key)

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KeyToOrder( key, component )

KeyToOrder

Returns an ORDER attribute expression list (for a VIEW) that mimics the specified key components.

key

The label of the KEY.

component

A numeric constant, variable, EQUATE, or expression that indicates the first component field to include in the expression. A value of one (1) specifies the first component; two (2) specifies the second component, etc.

The KeyToOrder method returns an ORDER attribute expression list (for a VIEW) that mimics the specified key components. The expression list includes the specified component field plus all the subsequent component fields in the key.

See the Language Reference for more information on ORDER.

Implementation:

The component defaults to one (1). The maximum length of the returned expression is 512 characters.

Return Data Type:     STRING

Example:

PROGRAM

INCLUDE('ABFILE.INC')                  !declare FileManager

MAP                                    !program map

END

 

GlobalErrors ErrorClass                 !declare GlobalErrors

Access:Order CLASS(FileManager)         !derive Access:Order

            END

 

Order FILE,DRIVER('TOPSPEED'),PRE(ORD),THREAD    !declare order file

IDKey   KEY(ORD:Cust,ORD:ID,ORD:Date),NOCASE,OPT,PRIMARY

Record  RECORD,PRE()

Cust     LONG

ID       LONG

Date     LONG

       END

     END

 

ClientView  VIEW(Order)                 !declare order view

            PROJECT(ORD:Cust,ORD:ID,ORD:Date)

           END

CODE

!program code

ClientView{PROP:Order}=Access:Order.KeyToOrder(ORD:IDKey,2)!set runtime view order

!ClientView{PROP:Order}='ORD:ID,ORD:Date'        !equivalent to this

OPEN(ClientView)

SET(ClientView)