Function _conType() | Xbase++

Determines the type of a container.

XPPAPIRET _conType(ContainerHandle, ULONG *ulType);

ContainerHandle ch;

Handle of any container.

ULONG *ulType

Pointer to a ULONG buffer into which the type of the container is written.

If the type of the container could be determined, NULL is returned. Otherwise the error which occurred is indicated by the return value (see the XPP_ERR_... macros).

The function _conType() determines the type of a container.

It should be noted that for some types more then one bit is masked in the return value. Furthermore, the numeric value representing a type may change in future Xbase++ versions. Because of these reasons the return value should be tested with one of the macros defined in the header file xpppar.h. The following table lists the macros and the types for which the macro evaluates to true:

Macro	Type	Meaning
XPP_IS_UNDEF()	XPP_UNDEF	NIL
XPP_IS_CHAR()	XPP_CHARACTER or XPP_MEMO	Character string
XPP_IS_MEMO()	XPP_MEMO	Memo character string
XPP_IS_NUM()	XPP_NUMERIC or XPP_DOUBLE	Numeric
XPP_IS_FLOAT()	XPP_DOUBLE	Floating point
XPP_IS_LOGIC()	XPP_LOGICAL	Logical
XPP_IS_DATE()	XPP_DATE	Date
XPP_IS_ARRAY()	XPP_ARRAY	Array
XPP_IS_BLOCK()	XPP_BLOCK	Code block
XPP_IS_OBJECT()	XPP_OBJECT	Object

/* 
 Read a parameter which either contains a character string 
 or a number. 
*/ 
#include <xppcon.h> 

ContainerHandle chs; 
BOOL            isRef; 
XPPAPIRET       xr; 
ULONG           type; 


chs = _conParam(<pList>, 1, &isRef); 
xr = _conType(chs, &type); 
if (xr != 0) 
{ 
/* ... error: no parameters were passed. */ 
} 
else 
{ 
/* <type> has the type of Parameter 1 */ 
if ( XPP_IS_CHAR(type) ) 
   if ( XPP_IS_MEMO(type) ) 
      /* 
         parameter is a memo ... 
      */ 
   else 
      /* 
         parameter is a character string (not a memo) ... 
      */ 
else if ( XPP_IS_NUM(type) ) 
   if ( XPP_IS_FLOAT(type) ) 
      /* 
         parameter is numeric and should 
         be read with _conGetND() ... 
      */ 
   else 
      /* 
         parameter is numeric and can be 
         read with _conGetN() ... 
      */ 
else 
   /* a different type ... */ 
} 
/* 
release the parameter container 
(if not passed by reference) 
*/ 
if (!isRef) 
_conRelease(chs);

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Function _conType() Foundation