Functions and Directives Functions and Directives

Function _conPutEmptyData() Foundation

Store the default null value of the passed datatype to its container.

Syntax
ContainerHandle _conPutEmptyData(ContainerHandle chDest,
                              ULONG xppType,
                              LONG length,
                              LONG decs);
Parameters
ContainerHandle chDest
Handle of a container that will contain the null value. If NULLCONTAINER is passed, a new container will be created.
ULONG xppType
Xbase++ datatype of the null value. Datatypes are defined in types.ch.
LONG length
In case the Xbase++ datatype is a memo field or a character string, this parameter is used to determine the length of the empty string that shall be created.
LONG decs
If the specified Xbase++ datatype is a numeric type, this parameter is used to determine the amount of decimals of the empty value.
Return

This function returns a container containing the new value.

Description

The function _conPutEmptyData() is used to assign a default null value of a certain Xbase++ datatype to a container. If a null value for the Xbase++ datatypes "C" or "M" is to be created, the resulting container will contain an empty string of a specified length. Logical values will default to .F. (FALSE). The date datatype will be emptied, and numeric values will default to zero.

Examples
#include <windows.h> 

#include "xppdef.h" 
#include "xpppar.h" 
#include "xppcon.h" 

XPPRET XPPENTRY MyCAPIFunction(XppParamList paramList) 
{  /* Declare and initialize variables */ 
ContainerHandle chTemp; 
ContainerHandle chResult = _conNewArray( 1, 4 ); 

/* Create NULL values.*/ 
chTemp = _conPutEmptyData( NULLCONTAINER, XPP_CHARACTER, 10, 0 ); 
if(_conArrayPut( chResult, chTemp, 1, 0 )) 
{ /* Error handling... */ 
} 

chTemp = _conPutEmptyData( chTemp, XPP_LOGICAL, 0, 0 ); 
if(_conArrayPut( chResult, chTemp, 2, 0 )) 
{ /* Error handling... */ 
} 

chTemp = _conPutEmptyData( chTemp, XPP_DATE, 0, 0 ); 
if(_conArrayPut( chResult, chTemp, 3, 0 )) 
{ /* Error handling... */ 
} 

chTemp = _conPutEmptyData( chTemp, XPP_NUMERIC, 10, 0 ); 
if(_conArrayPut( chResult, chTemp, 4, 0 )) 
{ /* Error handling... */ 
} 

/* Return created array. */ 
_conReturn( paramList, chResult ); 

/* Release containers. */ 
_conRelease( chTemp ); 
_conRelease( chResult ); 
}
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