This example continues from the previous one in which we retrieved the layout of the dynstruct ST_TEST into a flddefs() array, and then created a simple array, fnames$(), of member names. Here we’ll bind the defined dynstruct to a dynstruct variable, make assignments to members via the Simple Indirect syntax, and then retrieve members using the Indirect Deferred syntax with the help of the fnames$() array.
map1 status,i,4 ! status variable
map1 dstest, dynstruct ! dynstruct variable
map1 fields,i,4 ! # fields (see previous example)
map1 i,i,2 ! loop variable
dimx flddefs(10),ST_FLDDEF ! array of field info (see prev example)
dimx fnames$(0), T_MAX_DYNAME, auto_extend ! array of field names (see prev)
<define ST_TEST, retrieve flddefs(), create fnames$() per above examples>
status = Fn'Dynst'Bind("ST_TEST", dstest) ! bind ST_TEST Dynstruct to dstest
if status = 0 then ! success
! samples assignments using simple indirect syntax
dstest.sku = "SKU12345"
dstest.qty = 2
dstest.price.retail = 1.99
dstest.notes(1) = "steal this product"
dstest.notes(2) = "and live in infamy"
! sample retrieval/display using indirect deferred syntax
for i = 1 to fields
? dstest.@fnames$(i) ! warning: see notes below
next i
endif
Although the indirect deferred system is very convenient and indeed essential if the goal is to write totally generic code without any hard-coded references to specific dynamic structure members, there are a couple of complications which need to be considered when iterating through the fields by name; see the subtopics noted below.
Subtopics
