Example

The following example shows the code required to assign a custom function along with the code for the function itself. This example creates a Max function that accepts a variable number of parameters.

C++

// Assign MyMax function during initialization
FuncMaxProcInst = MakeProcInstance((FARPROC)SpreadFuncMaxProc, hInst);
SSAddCustomFunction(hWnd, "MYMAX", SS_CALC_VARPARAMS, FuncMaxProcInst);

// Callback function to perform calculation

BOOL CALLBACK SpreadFuncMaxProc(LPSS_VALUE Result, LPSS_VALUE Values, short ParamCnt);
{
double                Max;
double                MaxTemp;
short                i;

Result->Status = SS_VALUE_STATUS_EMPTY;
Result->Type = SS_VALUE_TYPE_LONG;

for (i = 0; i < ParamCnt; i++)
    if (Values[i].Status == SS_VALUE_STATUS_OK)
        {
        if (Values[i].Type == SS_VALUE_TYPE_DOUBLE)
            {
            Result->Type = SS_VALUE_TYPE_DOUBLE;
            MaxTemp = Values[i].Val.ValDouble;
            }
        else if (Values[i].Type==SS_VALUE_TYPE_LONG)
            MaxTemp = (double)Values[i].Val.ValLong;

        if (Result->Status == SS_VALUE_STATUS_EMPTY)
            Max = MaxTemp;
        else
            Max = max(Max, MaxTemp);

        Result->Status = SS_VALUE_STATUS_OK;
        }

// Check to see if the status is OK. Then determine if the
// result is a long or double and place it into the
// appropriate structure member.

if (Result->Status == SS_VALUE_STATUS_OK)
    if (Result->Type == SS_VALUE_TYPE_DOUBLE)
        Result->Val.ValDouble = Max;
    else
        Result->Val.ValLong = (long)Max;

return (TRUE);
}