on.main.table()

Syntax

void on.main.table( function_name [, ...] )

Description

This copies the contents current record of the main table to the record buffer of that table, saves the record, and executes the specified function. After that the saved record buffer is restored. This enables you to perform actions on the record contents without affecting the values in the table.

Arguments

function_name The name of the function that must be executed. The function must be of type void.

. . . Use these optional arguments to pass one or more arguments to the function.

Context

4GL library function.

You can use this function only in 4GL scripts. You cannot use it in the before.program section because the main table has not yet been defined at this point. The function is not relevant to programs of type 4.

Example
| Suppose you have a table to which you can add numbers only
| if a certain value is present in the main table

declaration:
long go_ahead

field.pctst999.number:
check.input:
on.main.table( check_number, 5 )
if not go_ahead then
set.input.error("pctst0003", 5) |"Number %d not present"
endif

functions:
function void check_number( long number )
{
select pctst999.*
from pctst999
where pctst999.number = :number
as set with 1 rows

selectdo
go_ahead = TRUE
selectempty
go_ahead = FALSE
endselect
return

}

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