_FREEFONT
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The _FREEFONT statement frees a font handle that was created by _LOADFONT.
Syntax
- _FREEFONT (fontHandle&)
Description
- Unloads fonts that are no longer in use or needed in order to free program memory and resources.
- You cannot free a font which is in use. Change the font to a QB64 default font size before freeing the handle (see example below).
- Predefined QB64 font handle numbers can be used before freeing a font:
- _FONT 8 - default font for SCREEN 1, 2, 7, 8 or 13
- _FONT 14 - default font for SCREEN 9 or 10
- _FONT 16 - default font for SCREEN 0 (Template:KW 80, 25 text only), 11 or 12
- _FONT 9, 15 and 17 are the double width versions of 8, 14 and 16 respectively in text SCREEN 0.
- If the font handle is invalid (equals -1 or 0), an error will occur. Check handle values before using or freeing them.
- You cannot free inbuilt/default QB64 fonts nor do they ever need freed.
Examples
Example 1: Previews and creates a file list of valid MONOSPACE TTF fonts by checking the _LOADFONT handle values.
SCREEN 12 path$ = "C:\WINDOWS\Fonts\" 'path to the font folder SHELL _HIDE "DIR /b " + path$ + "\*.ttf > TTFonts.INF" style$ = "monospace" 'set style to MONOSPACE OPEN "TTFonts.INF" FOR INPUT AS #1 'list of TTF fonts only OPEN "TTFMono.INF" FOR OUTPUT AS #2 'will hold list of valid MONOSPACE fonts DO UNTIL EOF(1): found = found + 1 LINE INPUT #1, font$ f& =_LOADFONT(path$ + font$, 30, style$) IF f& > 0 THEN 'check for valid handle values > 0 OK = OK + 1 PRINT #2, font$ _FONT f& 'will create error if handle is invalid! PRINT "Hello World!" PRINT: PRINT: PRINT font$; f& PRINT "Press any key." K$ = INPUT$(1) _FONT 16 'use QB64 default font to free tested font _FREEFONT f& 'returns an error if handle <= 0! CLS END IF PRINT IF K$ = CHR$(27) THEN EXIT DO LOOP CLOSE PRINT: PRINT: PRINT "Found"; found; "TTF files,"; OK; "can use Monospace," END |
Found 106 TTF files, 13 can use Monospace. |
Example 2: Using a _FREEFONT sub-procedure.
fontpath$ = ENVIRON$("SYSTEMROOT") + "\fonts\lucon.ttf" style$ = "MONOSPACE, ITALIC, BOLD" fontsize% = 20 _FONT 16 PRINT PRINT "This is the QB64 default _FONT 16! To change, press any key!" DO: SLEEP: LOOP UNTIL INKEY$ <> "" GOSUB ClearFont 'call will not free anything if font& = 0 font& = _LOADFONT(fontpath$, fontsize%, style$) IF font > 0 THEN _FONT font& 'NEVER try to load a font value less than 1! PRINT PRINT "A NEW _FONT style. To change to default, press any key!" DO: SLEEP: LOOP UNTIL INKEY$ <> "" GOSUB ClearFont 'call will free a valid font handle from memory END ClearFont: IF font& > 0 THEN _FONT 16 'change used font to the QB64 8x16 default font _FREEFONT font& PRINT: PRINT "The previous font was freed with _FREEFONT!" ELSE : PRINT: PRINT "_FREEFONT was not used!" END IF RETURN |
See also