Prototyping with Variables

Asked Feb 10 '16 at 18:56

Active Feb 10 '16 at 19:28

Viewed 25 times

I'm trying to create a capitalization function using prototyping but it only works with text strings and not injected variables. I don't know what I need to change to make it work.

String.prototype.capitalize = function() {
    return this.replace(/(?:^|\s)\S/g, function(a) { return a.toUpperCase(); });
};

That is my prototype but if i use it with var addition = document.getElementById('addition').capitalize(); it returns:

TypeError: document.getElementById('addition').capitalize is not a function. (In 'document.getElementById('addition').capitalize()', 'document.getElementById('addition').capitalize' is undefined)

Any thoughts as to how I can change this?

edited Feb 10 '16 at 19:28

Geek Num 88

5,264
2
22
35

asked Feb 10 '16 at 18:56

Matthew Walker

try this `var addition = document.getElementById('addition').toString().capitalize();` – Eugene Hauptmann Feb 10 '16 at 19:04
It at least got a return, but instead of a string i got `[object HTMLInputElement]` – Matthew Walker Feb 10 '16 at 19:14
ok, take a look here http://stackoverflow.com/questions/2470089/javascript-getelementbyid-and-convert-it-to-string it depends on what kind of DOM element it is, so in most cases you would want to go with `innerHTML` or `value` – Eugene Hauptmann Feb 10 '16 at 19:16
wow can't believe I didn't see I forgot `.value` thank you! – Matthew Walker Feb 10 '16 at 19:21
@www.eugenehp.tk That won't work at all. `toString` on an HTML element is likely to return something like `"[object HTMLDivElement]"`. – Feb 10 '16 at 20:02
@torazaburo see my comments from late about `value` – Eugene Hauptmann Feb 10 '16 at 20:03

Prototyping with Variables

0 Answers0