Why can't document methods be held in a function?
In JavaScript, you can set variables to hold certain functions and use them, like so:
var log = console.log;
log('foo');
But for some strange reason, you can't do that on most if not all document methods, such as querySelector:
var select = document.querySelector;
// causes the error: Uncaught TypeError: Illegal invocation
select('p'); <p>...</p>Why is that, and is there a workaround for it?
javascript function dom
asked Dec 31 '18 at 18:57
Eternal DarknessEternal Darkness
8331623
add a comment |
In JavaScript, you can set variables to hold certain functions and use them, like so:
var log = console.log;
log('foo');
But for some strange reason, you can't do that on most if not all document methods, such as querySelector:
var select = document.querySelector;
// causes the error: Uncaught TypeError: Illegal invocation
select('p'); <p>...</p>Why is that, and is there a workaround for it?
javascript function dom
asked Dec 31 '18 at 18:57
Eternal DarknessEternal Darkness
8331623
5
Because ofthis. Try withvar select = document.querySelector.bind(document);; stackoverflow.com/questions/2236747/…
– Federkun
Dec 31 '18 at 19:00
add a comment |
In JavaScript, you can set variables to hold certain functions and use them, like so:
var log = console.log;
log('foo');
But for some strange reason, you can't do that on most if not all document methods, such as querySelector:
var select = document.querySelector;
// causes the error: Uncaught TypeError: Illegal invocation
select('p'); <p>...</p>Why is that, and is there a workaround for it?
javascript function dom
asked Dec 31 '18 at 18:57
Eternal DarknessEternal Darkness
8331623
In JavaScript, you can set variables to hold certain functions and use them, like so:
var log = console.log;
log('foo');
But for some strange reason, you can't do that on most if not all document methods, such as querySelector:
var select = document.querySelector;
// causes the error: Uncaught TypeError: Illegal invocation
select('p'); <p>...</p>Why is that, and is there a workaround for it?
var select = document.querySelector;
// causes the error: Uncaught TypeError: Illegal invocation
select('p'); <p>...</p>var select = document.querySelector;
// causes the error: Uncaught TypeError: Illegal invocation
select('p'); <p>...</p>javascript function dom
javascript function dom
asked Dec 31 '18 at 18:57
Eternal DarknessEternal Darkness
8331623
asked Dec 31 '18 at 18:57
Eternal DarknessEternal Darkness
8331623
asked Dec 31 '18 at 18:57
Eternal DarknessEternal Darkness
8331623
asked Dec 31 '18 at 18:57
Eternal DarknessEternal Darkness
8331623
asked Dec 31 '18 at 18:57
Eternal DarknessEternal Darkness
8331623
8331623
5
Because ofthis. Try withvar select = document.querySelector.bind(document);; stackoverflow.com/questions/2236747/…
– Federkun
Dec 31 '18 at 19:00
add a comment |
5
Because ofthis. Try withvar select = document.querySelector.bind(document);; stackoverflow.com/questions/2236747/…
– Federkun
Dec 31 '18 at 19:00
5
5
Because of
this. Try with var select = document.querySelector.bind(document);; stackoverflow.com/questions/2236747/…– Federkun
Dec 31 '18 at 19:00
Because of
this. Try with var select = document.querySelector.bind(document);; stackoverflow.com/questions/2236747/…– Federkun
Dec 31 '18 at 19:00
add a comment |
1 Answer
1
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oldest
votes
The context seems to get lost. It's not bound with the document. Use it this way:
var select = document.querySelector.bind(document);
// Works!
console.log(select('p'));<p>...</p>You can see what a function is bound to, in JavaScript: What object javascript function is bound to (what is its "this")?.
answered Dec 31 '18 at 19:02
Praveen Kumar PurushothamanPraveen Kumar Purushothaman
133k23136183
add a comment |
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1 Answer
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active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
The context seems to get lost. It's not bound with the document. Use it this way:
var select = document.querySelector.bind(document);
// Works!
console.log(select('p'));<p>...</p>You can see what a function is bound to, in JavaScript: What object javascript function is bound to (what is its "this")?.
answered Dec 31 '18 at 19:02
Praveen Kumar PurushothamanPraveen Kumar Purushothaman
133k23136183
add a comment |
The context seems to get lost. It's not bound with the document. Use it this way:
var select = document.querySelector.bind(document);
// Works!
console.log(select('p'));<p>...</p>You can see what a function is bound to, in JavaScript: What object javascript function is bound to (what is its "this")?.
answered Dec 31 '18 at 19:02
Praveen Kumar PurushothamanPraveen Kumar Purushothaman
133k23136183
add a comment |
The context seems to get lost. It's not bound with the document. Use it this way:
var select = document.querySelector.bind(document);
// Works!
console.log(select('p'));<p>...</p>You can see what a function is bound to, in JavaScript: What object javascript function is bound to (what is its "this")?.
answered Dec 31 '18 at 19:02
Praveen Kumar PurushothamanPraveen Kumar Purushothaman
133k23136183
The context seems to get lost. It's not bound with the document. Use it this way:
var select = document.querySelector.bind(document);
// Works!
console.log(select('p'));<p>...</p>You can see what a function is bound to, in JavaScript: What object javascript function is bound to (what is its "this")?.
var select = document.querySelector.bind(document);
// Works!
console.log(select('p'));<p>...</p>var select = document.querySelector.bind(document);
// Works!
console.log(select('p'));<p>...</p>answered Dec 31 '18 at 19:02
Praveen Kumar PurushothamanPraveen Kumar Purushothaman
133k23136183
answered Dec 31 '18 at 19:02
Praveen Kumar PurushothamanPraveen Kumar Purushothaman
133k23136183
answered Dec 31 '18 at 19:02
Praveen Kumar PurushothamanPraveen Kumar Purushothaman
133k23136183
answered Dec 31 '18 at 19:02
Praveen Kumar PurushothamanPraveen Kumar Purushothaman
133k23136183
133k23136183
add a comment |
add a comment |
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5
Because of
this. Try withvar select = document.querySelector.bind(document);; stackoverflow.com/questions/2236747/…– Federkun
Dec 31 '18 at 19:00