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V_TYPE()
Return the type of data stored in a VLF
-------------------------------------------------------------------------------
Syntax
V_TYPE( <cPointer>,
<nArea> | <cAlias> ) -> cType
Arguments
<cPointer> is a six byte pointer-field (FlexFile's version of a
memo-field).
<nArea> or <cAlias> refers to the number or name of the target DBV
work area. If not specified, the current DBV work area is assumed.
Returns
V_TYPE() returns the type of the data that is pointed to by
<cPointer>. The possible types and their one character pneumonic
are detailed in the table under the V_REPLACE() function.
Description
V_TYPE() is similar to Clipper's TYPE() function. There are,
however, more "types" of data that can be stored to a VLF than in
a Clipper memory variable. For example, Clipper see's a Proclip
window handle as a numeric. Clipper's TYPE("pw_handle") function
would return a 'N'. However, if you save the Proclip window to a
VLF (See V_REPLACE()), the V_TYPE() function will return a 'P'.
Examples
// Setup seven variables of differing types.
LOCAL num_var ,;
chr_var ,;
date_var ,;
log_var ,;
arr_var ,;
ffa_var ,;
pcw_var
num_var = 5
chr_var = "This is a test"
date_var= DATE()
log_var = (.T.)
arr_var = { "Cindy", "Gail", "Edith" }
ffa_var = A_DECLARE( 'S', 5, 5 )// FlexFile double type
pcw_var = WNDCREATE( 5, 10 ) // Proclip window.
// Open a DBF file and its associated DBV file
USE dbf_file
V_USE( "dbv_file" )
// Replace the VLF with five different data types.
APPEND BLANK
REPLACE vlf WITH V_REPLACE( num_var, vlf )
? V_TYPE( vlf ) // Result: 'N'
REPLACE vlf WITH V_REPLACE( chr_var, vlf )
? V_TYPE( vlf ) // Result: 'C'
REPLACE vlf WITH V_REPLACE( date_var, vlf )
? V_TYPE( vlf ) // Result: 'D'
REPLACE vlf WITH V_REPLACE( log_var, vlf )
? V_TYPE( vlf ) // Result: 'L'
// Note: The replace here is V_AREPLACE() for Clipper 5.0
REPLACE vlf WITH V_AREPLACE( arr_var, vlf )
? V_TYPE( vlf ) // Result: 'A'
// Note: You must declare the type for a V_REPLACE()
// of a flexfile strongly typed array.
REPLACE vlf WITH V_REPLACE( ffa_var, vlf, , 'F' )
? V_TYPE( vlf ) // Result: 'F'
// Note: You must declare the type for a V_REPLACE()
// of a Proclip window handle.
REPLACE vlf WITH V_REPLACE( pcw_var, vlf, , 'P' )
? V_TYPE( vlf ) // Result: 'P'
See Also:
V_REPLACE()
V_RETRIEVE()
V_LEN()
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