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Tadjiev Codes
9,626 PointsWhat are the Void Functions in JavaScript? Does anyone know? Thanks
What are the Void Functions in JavaScript? Does anyone know? Thanks
2 Answers
Steven Parker
229,644 PointsWhere did you see this term? JavaScript doesn't implement a "void" type, but that term is used in other languages to declare functions that don't return any value.
In JavaScript, attempting to use a return value from a function that doesn't provide one does not cause an error but gives you "undefined" as the value.
Tadjiev Codes
9,626 PointsHi, I think you're right. Mostly I haven't found anything about this online beside this one here... Is it Javascript related?The link as follows === https://www.w3resource.com/javascript/operators/void.php Description The void operator is used to evaluate a JavaScript expression without returning a value.
Syntax
void (expression) void expression Example -1:
The following web document shows how the void operator is used.
HTML Code
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset=utf-8>
<title>JavaScript void operator example</title>
</head>
<body>
<a href="javascript:void(alert('Thank you.'))">Click here to see a message</a>
</body>
</html>
Steven Parker
229,644 PointsI'd never run into that before, but sure enough, JavaScript has a "void" operator!
I sure can't think of any reason to use it, though. If you actually need an undefined value, you can use the keyword "undefined", and if you want to evaluate an expression but don't care about the result, you can simply ignore it.