# Arrays of Dynstructs

> [HTML Version](arraysofdynstructs.htm)

As noted above in [Declare a DYNSTRUCT Variable](declare_a_dynstruct.htm.md), the dynstruct type currently only supports mapped scalar variables; no arrays, mapped or dimx. However, as also noted, you can work around this limitation by copying freely between dynstructs and arrays of traditional structures or X variables. In this example, we retrieve instances of ST\_TEST structures—defined in the example [Define a Dynstruct from a String](define_a_dynstruct.htm.md)—from a function, copying each to an array of type X that was previously dimensioned to match the size of ST\_TEST. Then we reverse the operation, copying elements out of the array back into the scalar dynstruct variable to print the members.

map1 dsdef\$,s,0             \! string to hold definition source

map1 fields,i,2             \! # fields (signed to allow error codes)

map1 stsize,b,4             \! size of the structure

map1 errmsg\$,s,100          \! error messages

map1 ds, DYNSTRUCT          \! var to contain the dynstruct ST\_TEST



\! assume dsdef\$ string already built to define ST\_TEST (see first example)

\! now define it and get the size



fields = Fn'Dynst'Define(dsdef\$,stsize,"ST\_TEST",errmsg\$) 

if fields > 0 then

    dimx testarray(0), X, stsize, auto\_extend   \! array to match dynstruct size



    do while <some condition>

        ds = Fn’Get’Structure’Data\$("ST\_TEST")  \! get data into the ds from somewhere

        i += 1

        testarray(i) = ds             \! copy it into our unformatted array 

    loop



    \! now reverse process, copying from the X array to our ds var

    do while i > 0 

        ds = testarray(i)  
     ? ds.sku  
     ? ds.price.retail  
     ? ds.notes(1) 

        ? ds.@fname

        \! etc

    Loop

Endif