How to Determine If All Elements in an Array Are Empty

ID: Q103088

2.00 2.50 2.50a | 2.50 2.50a 3.00

MS-DOS          | WINDOWS

The information in this article applies to:

Microsoft Visual FoxPro for Windows, version 3.0
Microsoft FoxPro for MS-DOS, versions 2.0, 2.5, and 2.5a
Microsoft FoxPro for Windows, versions 2.5 and 2.5a

SUMMARY

To determine if an entire array is empty, you can use the function shown below.

NOTE: There isn't a FoxPro function written for this purpose. The EMPTY() function comes close, but it will not return a correct answer if an array element that is not the first element in the array is populated with data.

MORE INFORMATION

The following function will return a logical false if any element in the entire array is populated with anything other than .F.:

   FUNCTION aempty
   PARAMETERS aname
   FOR pass = 1 to ALEN(aname) STEP 1
   retval = EMPTY(aname(pass))
   IF retval
      LOOP
   ELSE
       RETURN retval
   ENDIF
   ENDFOR

This function takes a single parameter <arrayname>. The syntax to call this function is as follows:

   SET UDFPARMS TO REFERENCE
   DIMENSION x(10)
   x(5) = "junk"
   ? aempty(x)

NOTE: The elements in any array will initially be false (.F.) by default. Therefore, any element with a logical value of .F. is considered empty.

Additional reference words: VFoxWin 3.00 FoxDos FoxWin 2.50 2.00 2.50a KBCategory: KBSubcategory: FxprgGeneral

Keywords          : kbcode FxprgGeneral 
Version           : 2.00 2.50 2.50a | 2.50 2.50a 3.0
Platform          : MS-DOS WINDOWS