Do java script or jquery has a function like inArraykey?

Question

As far as I know jQuery has a function inArrary which is apply like the following

$.inArray(value, array); it return -1 if not in array

However, this function only apply to value and is not suitable for the multidimension array

eg . fruit [ apple,orange]

For instance, if I have an array like this

eg. fruit [apple => [red,$1], orange => [orange,$5]]

I have to check whether a value exist (eg. banana) as the array key, are there any function appropriate in this case?

your question/example is not really clear. Are you referring to indexOf() ? — mika
– mika, Commented Feb 8, 2013 at 2:28

user229044 · Accepted Answer · 2013-02-12 14:54:06Z

1

Arrays cannot have string keys in JavaScript. Only objects can.

If you want to see if an object contains has a key banana, you can simply test that it isn't undefined:

if (myObject.banana != undefined) {

}

... or use hasOwnProperty, which may be better in cases when you may have initialized a property to undefined:

if (myObject.hasOwnProperty("banana")) {

}

answered Feb 8, 2013 at 2:26

user229044♦

241k41 gold badges347 silver badges350 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

I'd use 'banana' in myObject. Also, I'd use !== undefined, as myObject.banana can be null.

"Arrays cannot have string keys" - but they can have properties since they are still objects :)

really helpful, that's all I want

You should go with hasOwnProperty - not having a property is not the same as that property existing and being undefined.