Pass an array to a method

[Ryan Mott]

Has anyone been successful in passing an array to a method in a class? I am receiving the error “Error 422, scalar variable expected”. I also tried passing a pointer to the array, but this resulted in a crash. Any ideas would be appreciated. If I find a solution (which is probably something simple), I will post it.

[Ryan Mott]

Here is a simple example of the problem:

#COMPILE EXE
#DIM ALL

CLASS cTest
    INTERFACE iTest
        INHERIT IUNKNOWN
        
        METHOD readArray(BYVAL p AS STRING POINTER)
            MSGBOX @p[0]
        END METHOD
        
    END INTERFACE

END CLASS

FUNCTION PBMAIN () AS LONG
    DIM i AS DWORD
    DIM p AS STRING POINTER
    DIM a(2) AS STRING
    
    a(0) = "Test 1"
    a(1) = "Test 2"
    a(2) = "Test 3"
    
    p = VARPTR(a(0))
    
    DIM c AS iTest
    c = CLASS "cTest"
    
    c.readArray(p)
    
END FUNCTION

[Michael Mayerhoffer]

You can pass the array as an Variant

LET vrntvar = array()

[Ryan Mott]

Thanks Michael. I figured that variants would be the solution.

#COMPILE EXE
#DIM ALL

CLASS cTest
    INTERFACE iTest
        INHERIT IUNKNOWN

        METHOD readArray(v AS VARIANT)
            DIM a(2) AS STRING
            LET a() = v
            MSGBOX a(0)
        END METHOD

    END INTERFACE
END CLASS

FUNCTION PBMAIN () AS LONG
    DIM i AS DWORD
    DIM a(2) AS STRING
    DIM v AS VARIANT

    a(0) = "Test 1"
    a(1) = "Test 2"
    a(2) = "Test 3"
    
    LET v = a()

    DIM c AS iTest
    c = CLASS "cTest"

    c.readArray(v)
END FUNCTION

[José Roca]

REDIM AT is your friend.

#COMPILE EXE
#DIM ALL

CLASS cTest
    INTERFACE iTest
        INHERIT IUNKNOWN
        
        METHOD readArray(BYVAL p AS DWORD, BYVAL n AS DWORD)
            REDIM x(n-1) AS STRING AT p
            MSGBOX x(0)
        END METHOD
        
    END INTERFACE

END CLASS

FUNCTION PBMAIN () AS LONG
    DIM i AS DWORD
    DIM p AS STRING POINTER
    DIM a(2) AS STRING
    
    a(0) = "Test 1"
    a(1) = "Test 2"
    a(2) = "Test 3"
    
    p = VARPTR(a(0))
    
    DIM c AS iTest
    c = CLASS "cTest"
    
    c.readArray(p, 3)
    
END FUNCTION

[Ryan Mott]

Excellent solution. Thanks Jose.