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V_VLF2FILE()
Create a DOS file and fill it with the contents of a VLF
-------------------------------------------------------------------------------
Syntax
V_VLF2FILE( <cFileName>,
<cPointer>,
<cMode> ) -> lSuccess
Arguments
<cFileName> is the name of a file to append to or overwrite with
the data from a VLF associated with <cPointer>.
<cPointer> is a six byte pointer-field (FlexFile's version of a
memo-field).
<cMode> is a character code telling FlexFile to <A>ppend or
<O>verwrite any existing file with the same name as <cFileName>.
The default mode is <A>ppend.
Returns
V_VLF2FILE() returns (.T.) if the data was copied successfully,
otherwise, it returns (.F.).
Description
V_VLF2FILE() copies a Variable Length Field from a DBV type file
to a DOS file. This is particularly useful when using graphics
applications from within Clipper that require individual files for
images.
Examples
// Setup variable
LOCAL pic_name
// Open a DBF, NTX and DBV library of graphics images.
USE ( pic_lib ) INDEX ( pic_lib )
V_USE( pic_lib )
// Allow the user to enter the name of a graphic image
// to view, create a temporary disk file, print the
// file to screen.
WHILE ( .T. )
pic_name = SPACE(11)
@ 5, 5 SAY "Enter the image name to view: " GET pic_name
SEEK pic_name
IF FOUND()
// Write DBV data to a temporary file.
V_VLF2FILE( "graphic.pic", vlf_ptr )
// Use one of the graphic function libraries to retrieve a file.
file2graph( 0, "graphic.pic" )
INKEY(0)
ELSEIF LASTKEY() == 27
EXIT
ELSE
? "Image not found"
ENDIF
ENDDO
See Also:
V_FILE2VLF()
V_REPLACE()
V_DELETE()
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