FontFaceSet.check()
The check()
method of the FontFaceSet
returns whether all
fonts in the given font list have been loaded and are available.
Syntax
check(font)
check(font, text)
Parameters
font
-
a font specification using the CSS value syntax, for example
"italic bold 16px Roboto"
text
-
limit the font faces to those whose Unicode range contains at least one of the characters in text. This does not check for individual glyph coverage.
Return value
A Boolean
value that is true
if the font list is available.
The method returns true
if the font list contains system or nonexistent fonts. This prevents websites from identifying users by the fonts they have installed.
Examples
In the following example, the first line will print true
if the Courier font is available at 12px
. The second line will print true
if the font MyFont
contains the "ß" character.
console.log(document.fonts.check("12px courier"));
console.log(document.fonts.check("12px MyFont", "ß"));
If the font given in the font specification does not exist, this function returns false
:
console.log(document.fonts.check("12px NonExistingFont"));
// false
Specifications
Specification |
---|
CSS Font Loading Module Level 3 # dom-fontfaceset-check |
Browser compatibility
BCD tables only load in the browser