Are dashes allowed in javascript property names?
JavascriptJavascript Problem Overview
I was looking at http://docs.jquery.com/Plugins/Authoring#Defaults_and_Options to create a simple plugin for jQuery. Following the section about options and settings, I did the following, which didn't work (the script quit when it encountered the setting).
var settings = {
'location' : 'top',
'background-color': 'blue'
}
...
$this.css('backgroundColor', settings.background-color); // fails here
Once I removed the dash from the background color, things work properly.
var settings = {
'location' : 'top',
'backgroundColor': 'blue' // dash removed here
}
...
$this.css('backgroundColor', settings.backgroundColor);
Am I missing something, or are the jQuery docs wrong?
Javascript Solutions
Solution 1 - Javascript
no. the parser will interpret it as the subtract operator.
you can do settings['background-color']
.
Solution 2 - Javascript
Change settings.background-color
to settings['background-color']
.
Variables cannot contain -
because that is read as the subtract operator.
Solution 3 - Javascript
Dashes are not legal in javascript variables. A variable name must start with a letter, dollar sign or underscore and can be followed by the same or a number.
Solution 4 - Javascript
You can do something like this:
var myObject = {
propertyOne: 'Something',
'property-two': 'Something two'
}
for (const val of [ myObject.propertyOne, myObject['propertyOne'],
myObject['property-two']
]){
console.log(val)
}
Solution 5 - Javascript
You can have dashes in strings. If you really wanted to keep that dash, you'd have to refer to the property using brackets and whatnot:
$this.css('backgroundColor', settings['background-color']);