_ALen( ) API Library Routine Example

The following example provides a Visual FoxPro API routine for each of the three possible mode values.

Visual FoxPro Code

SET LIBRARY TO ALEN  
DIMENSION a[10, 11]
? ALENELEM(@a)  && returns 110
? ALENSUB1(@a)  && returns 10
? ALENSUB2(@a)  && returns 11

DIMENSION b[3]
? ALENELEM(@b)  && returns 3
? ALENSUB1(@b)  && returns 3
? ALENSUB2(@b)  && returns 0; no second subscript

c = .F.
? ALENELEM(@c)  && returns -1 because variable "c" is not an array
? ALENSUB1(@c)  && returns -1 because variable "c" is not an array
? ALENSUB2(@c)  && returns -1 because variable "c" is not an array

C Code

#include <pro_ext.h>

void FAR alenElem(ParamBlk FAR *parm)
{
   _RetInt(_ALen(parm->p[0].loc.l_NTI, AL_ELEMENTS), 10);
}

void FAR alenSub1(ParamBlk FAR *parm)
{
   _RetInt(_ALen(parm->p[0].loc.l_NTI, AL_SUBSCRIPT1), 10);
}

void FAR alenSub2(ParamBlk FAR *parm)
{
   _RetInt(_ALen(parm->p[0].loc.l_NTI, AL_SUBSCRIPT2), 10);
}

FoxInfo myFoxInfo[] = {
   {"ALENELEM", (FPFI) alenElem, 1, "R"},
   {"ALENSUB1", (FPFI) alenSub1, 1, "R"},
   {"ALENSUB2", (FPFI) alenSub2, 1, "R"},
};
FoxTable _FoxTable = {
   (FoxTable FAR *) 0, sizeof(myFoxInfo)/sizeof(FoxInfo), myFoxInfo
};